tag:blogger.com,1999:blog-52321617160298933812024-03-08T08:13:11.103-08:00Philosophy of Space ExploratonA discussion of several important philosophical problems concerning the justification of space exploration and other conceptual puzzles that arise from the actual and potential practice of space science (e.g. travel at relativistic velocities or faster than light, a runaway green house effect on Venus, terraforming of Mars, extraterrestrial life and intelligent civilizations). The discussion is taken from my manuscript The Dimming of Starlight.Ryan Munevarhttp://www.blogger.com/profile/01819338408967576382noreply@blogger.comBlogger82125tag:blogger.com,1999:blog-5232161716029893381.post-59110976055383616152012-02-27T16:48:00.000-08:002012-02-27T16:49:32.035-08:00Space Exploration and the Humanities<p class="MsoNormal" style="margin-bottom:0in;margin-bottom:.0001pt;line-height:normal"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">Space Exploration and the Humanities</span></b></p> <p class="MsoNormal" style="margin-bottom:0in;margin-bottom:.0001pt;line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p> <p class="MsoNormal" style="margin-bottom:0in;margin-bottom:.0001pt;line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">Good news for those interested in the relationship between space exploration and the humanities and social sciences.<span> </span>The book <i>Imagining Outer Space</i>, edited by Alexander CT Geppert is finally out.<span> </span>You may remember that I wrote about it some time ago.<span> </span>You may want to take a look at the website of Palgrave MacMillan, the publisher:</span></p> <table border="0" cellpadding="0"> <tbody><tr> <td style="width:6.55pt;padding:0in 0in 0in 0in" width="9"><br /></td> <td style="width:1.0pt;padding:0in 0in 0in 0in" width="1"> <p class="MsoNormal" style="margin-bottom:0in;margin-bottom:.0001pt;line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""><img alt="https://mail.google.com/mail/images/cleardot.gif" height="1" width="1" /><span> </span><img alt="https://mail.google.com/mail/images/cleardot.gif" height="1" width="1" /></span><span style="font-size:12.0pt;font-family:"Times New Roman","serif""></span></p> </td> </tr> </tbody></table> <p class="MsoNormal"><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif""><a href="http://www.palgrave.com/products/title.aspx?PID=364196" target="_blank">http://www.palgrave.com/<wbr>products/title.aspx?PID=364196</a></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif""> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif"">On related news, "Envisioning Limits: Outer Space and the End of Utopia," a sequel conference to the "Imagining Outer Space" symposium, <span> </span>which was the basis of the book, will take place in Berlin at the end of April. Please see <a href="http://limits.geschkult.fu-berlin.de/" target="_blank">http://limits.geschkult.<wbr>fu-berlin.de</a> for further details, some of which are provided below in this posting:</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif""> </span></p> <p class="MsoNormal" style="text-align:center;line-height:normal" align="center"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">Envisioning Limits:<br />Outer Space and the End of Utopia</span></b></p> <p class="MsoNormal" style="text-align:center;line-height:normal" align="center"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">Berlin, 19 - 21 April 2012</span></b></p> <p class="MsoNormal" style="line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p> <table style="width:100.0%;border:outset white 1.0pt" border="1" cellpadding="0" width="100%"> <tbody><tr> <td style="width:353.25pt;padding:.75pt .75pt .75pt .75pt" valign="top" width="471"> <p class="MsoNormal" style="line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> <span><img alt="NASA" border="0" height="236" width="369" /></span></span></p> </td> <td style="width:156.0pt;padding:.75pt .75pt .75pt .75pt" valign="top" width="208"> <p class="MsoNormal" style="line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p> <p class="MsoNormal" style="line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p> <p class="MsoNormal" style="line-height:normal"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> Home</span></b></p> <p class="MsoNormal" style="line-height:normal"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/program.html" title="program" target="_blank">Program</a> (><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/EL_-_Program_2012-02-09.pdf" title="Program pdf " target="_blank">pdf</a>)</span></b></p> <p class="MsoNormal" style="line-height:normal"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html" title="abstracts" target="_blank">Abstracts</a> (><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/EL_-_Abstracts_2012-02-09.pdf" title="Abstracts pdf" target="_blank">pdf</a>)</span></b></p> <p class="MsoNormal" style="line-height:normal"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html" title="bios" target="_blank">Bios</a> (><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/EL_-_Bios_2012-02-09.pdf" title="Bios pdf" target="_blank">pdf</a>)</span></b></p> <p class="MsoNormal" style="line-height:normal"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></b></p> <p class="MsoNormal" style="line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p> <p class="MsoNormal" style="line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p> <p class="MsoNormal" style="line-height:normal"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> updated: 10.02.2012</span></b></p> </td> </tr> </tbody></table> <p class="MsoNormal" style="line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""><br />If space exploration is understood as not just one of the twentieth century’s most prestigious feats of engineering, but also a central theme in period visions of the future and utopias, then how might we understand the transition from the 1960s to the 1970s, with its emphasis on reduced possibilities and limitations to progress? The conference aims to shift the focus away from explanations of transition from Cold War contexts and produce more nuanced narratives: from the familiar struggle between two superpowers, namely the USA and the former USSR, to distinctly West-European perspectives, and from political to socio-cultural dimensions of the Space Age. How were limits created, challenged and maintained? And in what sense was outer space invoked to transform cultural boundaries and how were these conveyed to different audiences? The conference will look at utopia not as a socio-cultural objective but rather as a process. Through defining limitless opportunities afforded by outer space, advocates of space exploration not only opened up new possibilities for accelerating or even surpassing human development, but also delineated the historicity and limitations of the imagination.</span></p> <p class="MsoNormal" style="line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">Conference speakers include Debbora Battaglia (Mount Holyoke College), Martin Collins (National Air and Space Museum), David A. Kirby (University of Manchester), John Krige (Georgia Institute of Technology), Agnes Meyer-Brandis (Universität der Künste Berlin), Roger D. Launius (National Air and Space Museum) and Helmuth Trischler (Deutsches Museum).</span></p> <p class="MsoNormal" style="line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">For further information and to register please contact the conveners Alexander C.T. Geppert, William R. Macauley and Daniel Brandau at <a href="mailto:astrofuturismus@fu-berlin.de" target="_blank">astrofuturismus@fu-berlin.de</a>. There is a conference fee of 50 € (concessions 25 €) to cover the cost of food, drinks and refreshments during the event.</span></p> <p class="MsoNormal" style="line-height:normal"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">Conference Venue</span></b></p> <p class="MsoNormal" style="line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""><a href="http://www.harnackhaus-berlin.mpg.de/eng-index.htm" target="_blank">Harnack-Haus der Max-Planck-Gesellschaft</a><br />Ihnestrasse 16-20<br />D-14195 Berlin</span></p> <table style="width:100.0%;border:outset white 1.0pt" border="1" cellpadding="0" width="100%"> <tbody><tr> <td style="width:393.75pt;padding:.75pt .75pt .75pt .75pt" valign="top" width="525"> <h3><strong><span style="font-size:12.0pt">THURSDAY, 19 April 2012</span></strong><span style="font-size:12.0pt"></span></h3> <h2><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif"">09.00 Introduction</span></h2> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Geppert" title="Alexander C.T. Geppert" target="_blank">Alexander C.T. Geppert</a>, <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Brandau" title="Daniel Brandau" target="_blank">Daniel Brandau</a>, <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Macauley" title="William R. Macauley" target="_blank">William R. Macauley</a>:<br /> <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Geppert" title="1970s, Western Europe and Questions of Limits" target="_blank"><em>The 1970s, Western Europe and the Delineation of Space</em></a></p> <h2><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif"">09.30 Feature Presentation I</span></h2> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Collins" title="Martin Collins" target="_blank">Martin Collins</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Collins" title="Ambiguities of the 1970s" target="_blank"><em>Ambiguities of the 1970s: Spaceflight and the Problem of Historically Interpreting the In-Between Decade</em></a></p> <h2><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif"">11.00 Panel I: Transitions</span></h2> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Jenks" title="Andrew Jenks" target="_blank">Andrew Jenks</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Jenks" title="Transnational History and Human Spaceflight" target="_blank"><em>Transnational History and Human Spaceflight</em></a></p> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Millard" title="Doug Millard" target="_blank">Doug Millard</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Millard" title="Were the 1970s a Period of Transition?" target="_blank"><em>Were the 1970s a Period of Transition for the History of Britain’s Exploration of Space?</em></a></p> </td> <td style="width:115.5pt;padding:.75pt .75pt .75pt .75pt" valign="top" width="154"> <p> </p> <p> </p> <h5><span style="font-size:12.0pt"> <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/index.html" title="home" target="_blank">Home</a></span></h5> <h5><span style="font-size:12.0pt"> Program (<a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/EL_-_Program_2012-02-09.pdf" title="Program pdf" target="_blank">pdf</a>)</span></h5> <h5><span style="font-size:12.0pt"> <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html" title="abstracts" target="_blank">Abstracts</a> (<a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/EL_-_Abstracts_2012-02-09.pdf" title="Abstracts pdf" target="_blank">pdf</a>)</span></h5> <h5><span style="font-size:12.0pt"> <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html" title="bios" target="_blank">Bios</a> (<a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/EL_-_Bios_2012-02-09.pdf" title="Bios pdf" target="_blank">pdf</a>)</span></h5> <p> </p> <p> </p> <p> </p> <h6><span style="font-size:12.0pt"><br /> updated: 10.02.2012</span></h6> </td> </tr> </tbody></table> <p>Chair: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Nolte" title="Paul Nolte" target="_blank">Paul Nolte</a></p> <h2><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif"">14.00 Panel II: Pictures</span></h2> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Poole" title="Robert Poole" target="_blank">Robert Poole</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Poole" title="2001: A Space Odyssey" target="_blank"><em>'2001: A Space Odyssey': Space Travel and the Ends of Progress</em></a></p> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#B%C3%BClow" title="Ralf Bülow" target="_blank">Ralf Bülow</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#B%C3%BClow" title="The X Files" target="_blank"><em>The</em> X <em>Files: Reading a West German Sci-Tech Magazine from 1969 to 1973</em></a></p> <p>Chair: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Weber" title="Thomas P. Weber" target="_blank">Thomas P. Weber</a></p> <h2><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif"">16.00 Panel III: Laws</span></h2> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Follis" title="Luca Follis" target="_blank">Luca Follis</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Follis" title="Beyond Law's Frontier" target="_blank"><em>Beyond Law’s Frontier: The Normative Imaginary of Outer Space</em></a></p> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Pop" title="Virgiliu Pop" target="_blank">Virgiliu Pop</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Pop" title="The Moon Agreement" target="_blank"><em>The Moon Agreement and the Beginning of Utopia</em></a></p> <p>Chair: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Becker" title="Peter Becker" target="_blank">Peter Becker</a></p> <h2><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif"">19.00 Feature Presentation II</span></h2> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Meyer-Brandis" title="Agnes Meyer-Brandis" target="_blank">Agnes Meyer-Brandis</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Meyer-Brandis" title="Agnes Meyer-Brandis" target="_blank"><em>Space Traveling: A Performence-Lecture Examining Real Utopian Aspects of Interplanetary Exchange of Idea and Matter</em></a></p> <h3><span style="font-size:12.0pt"><br /><strong>FRIDAY, 20 April 2012</strong></span></h3> <h2><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif"">09.00 Feature Presentation III</span></h2> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Krige" title="John Krige" target="_blank">John Krige</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Krige" title="Blowback, Lift Off" target="_blank"><em>Blowback, Lift Off: The Rise of Ariane and the Decline of U.S. Monopoly of Access to Space in the 1970s</em></a></p> <p>Chair: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Macauley" title="William R. Macauley" target="_blank">William R. Macauley</a></p> <h2><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif"">10.15 Panel IV: Politics</span></h2> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Hersch" title="Matthew H. Hersch" target="_blank">Matthew H. Hersch</a>: <em>'</em><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Hersch" title="On the Edge of Forever" target="_blank"><em>On the Edge of Forever:' 1972 and the New American Space Consensus</em></a></p> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Maher" title="Neil M. Maher" target="_blank">Neil M. Maher</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Maher" title="Ground Control" target="_blank"><em>Ground Control: Space Technology, Environmentalism, and Détente Across the Developing World</em></a></p> <p>Chair: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Benson" title="Etienne Benson" target="_blank">Etienne Benson</a></p> <h2><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif"">13.00 Panel V: Texts</span></h2> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Kl%C3%A4ger" title="Florian Kläger" target="_blank">Florian Kläger</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Kl%C3%A4ger" title="Reading into the Stars" target="_blank"><em>Reading into the Stars: Cosmology and Self-Reflexivity in the British Novel of the 1970s</em></a></p> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Idzior" title="Aleksandra Idzior" target="_blank">Aleksandra Idzior</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Idzior" title="Images of Extraterrestrial Life" target="_blank"><em>Images of Extraterrestrial Life and Designs for 'Out-of-Space' in Poland during the 1960s and 1970s</em></a></p> <p>Chair: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Schwartz" title="Matthias Schwartz" target="_blank">Matthias Schwartz</a></p> <h2><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif"">15.00 Panel VI: Aesthetics</span></h2> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Vatsella" title="Christina Vatsella" target="_blank">Christina Vatsella</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Vatsella" title="Artworks in Orbit" target="_blank"><em>Artworks in Orbit: The Satellite Art Projects</em></a></p> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Bjornvig" title="Thore Bjornvig" target="_blank">Thore Bjørnvig</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Bjornvig" title="Unlimited Play in a World of Limits" target="_blank"><em>Unlimited Play in a World of Limits: The Lego Classic Space Theme, 1978-80</em></a></p> <p>Chair: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Schm%C3%B6lders" title="Claudia Schmölders" target="_blank">Claudia Schmölders</a></p> <h2><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif"">17.00 Panel VII: Prospects</span></h2> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Ailleris" title="Philippe Ailleris" target="_blank">Philippe Ailleris</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Ailleris" title="Red Soil, Phonograph Records and United Nations Resolution" target="_blank"><em>Red Soil, Phonograph Records and United Nations Resolution 33/426: Our 1970s Extraterrestrial Heritage</em></a></p> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Vertesi" title="Janet Vertesi" target="_blank">Janet Vertesi</a> and <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Messeri" title="Lisa Messeri" target="_blank">Lisa Messeri</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Vertesi" title="The Greatest Mission Never Flown" target="_blank"><em>The Greatest Mission Never Flown: Mars Sample Return, Terrestrial Planet Finder, and the Limits of Utopia</em></a></p> <p>Chair: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Battaglia" title="Debbora Battaglia" target="_blank">Debbora Battaglia</a></p> <h3><span style="font-size:12.0pt"><br /><strong>SATURDAY, 21 April 2012</strong></span></h3> <h2><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif"">09.00 Panel VIII: Habitats</span></h2> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#McCray" title="W. Patrick McCray" target="_blank">W. Patrick McCray</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#McCray" title="Gerard O'Neill's Visioneering" target="_blank"><em>Gerard O'Neill’s Visioneering of the 'High Frontier</em></a><em>'</em></p> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Munevar" title="Gonzalo Munevar" target="_blank">Gonzalo Munévar</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Munevar" title="Space Colonies and their Critics" target="_blank"><em>Space Colonies and their Critics</em></a></p> <p>Chair: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Brandstetter" title="Thomas Brandstetter" target="_blank">Thomas Brandstetter</a></p> <h2><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif"">11.00 Panel IX: Transcendence</span></h2> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Westwick" title="Peter J. Westwick" target="_blank">Peter J. Westwick</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Westwick" title="From the Club of Rome to Star Wars" target="_blank"><em>From the Club of Rome to Star Wars: The Era of Limits, Space Colonization, and the Origins of the Strategic Defense Initiative</em></a></p> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Launius" title="Roger D. Launius" target="_blank">Roger D. Launius</a>: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/abstracts.html#Launius" title="Human Spaceflight as Religion" target="_blank"><em>Human Spaceflight as Religion in the Aftermath of the Space Race</em></a></p> <p>Chair: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Trischler" title="Helmuth Trischler" target="_blank">Helmuth Trischler</a></p> <h2><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif"">14.00 Conclusion</span></h2> <p><a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Kirby" title="David A. Kirby" target="_blank">David A. Kirby</a>: <em>General Comment</em></p> <p>Chair: <a href="http://www.geschkult.fu-berlin.de/e/astrofuturismus/veranstaltungen/C_Envisioning/bios.html#Geppert" title="Alexander C.T. Geppert" target="_blank">Alexander C.T. Geppert</a></p> <h2><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman","serif"">16.00 End</span></h2> <p class="MsoNormal" style="line-height:normal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-3981610760519339582012-02-05T00:41:00.000-08:002012-02-05T00:43:03.308-08:00Play, Human Nature and Exploration: Some Speculations<p class="MsoNormal" style="line-height:12.0pt"><b>Chapter 11B</b></p> <p class="MsoNormal" style="line-height:12.0pt"><b> </b></p> <p class="MsoNormal" style="line-height:12.0pt"><b>Play, Human Nature and Exploration: Some Speculations</b></p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">That delight of finding things out, of satisfying curiosity, may on occasion be a search for beauty, as Poincare may have thought, but on the whole it is more properly associated with play. This is not to deny that the search for beauty may itself be a form of play. <span> </span>Nor is it to deny that in play we may find beauty ‑‑a claim to which many people who have engaged in sports would testify.<span> </span>In any event, there is nothing mysterious in that nature should have made us such that we enjoy exercising our skills and developing our talents through play.</p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">When an animal can grow only in a very specific environment, play is probably not very crucial.<span> </span>The animal may be better off rehearsing the specific tasks that will be needed for survival later on.<span> </span>But to the extent that an animal is to meet an open‑ ended environment, it pays to develop all sort of perceptual and motor skills in many combinations.<span> </span>This flexibility will permit the animal to adapt to a greater range of environments.<span> </span>The difference between fixed exercises, such as calisthenics, and play is precisely that whereas specific traits are developed in the first, an exploration of the individuals' abilities takes place in the second. </p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">Although this is not the place to embark into a fully fledged biology of play, at least two qualifications are in order.<span> </span>The first is that there need be no connection between the animal having played while young and its exhibiting a very flexible response later in life.<span> </span>A species may not be restricted to any specific environment, in which case play by its young may be very advantageous to it. But once that species finds itself in a particular environment, the flexibility of its members allows them to try out ways of developing their skills that eventually lead to an optimal interaction with that environment.<span> </span>As that begins to happen, the range of behavior begins to narrow as well.<span> </span>Presumably the adult animals become fairly well adapted and can afford to be as rigid as those other animals that were "designed" for that specific environment. </p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">Thus we see that ravens, for example, grow up to be scavengers in some habitats and predators in others.<span> </span>The species is flexible, and its playing young are flexible, but the individual adults need not be.<span> </span>In a species such as homo sapiens, in which the adult may continue to deal with an open environment, the advantages of prolonged youth and of flexibility in the adult are evident.<span> </span>And indeed contemporary biology ascribes a "neotonous" nature to humans (neoteny permits the retention of immature characters in adulthood).</p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">The second qualification is this.<span> </span>In perfecting its responses to the pressing demands of a specific environment, an animal may receive direct and immediate dividends. The rationale for perfecting those responses is thus obvious.<span> </span>But what mechanisms might evolve to motivate the rehearsal of skills whose application is indirect and far in the future?<span> </span>The question is no longer whether play is biologically advantageous to some species.<span> </span>The answer to that question is yes.<span> </span>The present question concerns rather how the individual animals are led to play. </p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">This demand for a mechanism can be met ‑‑ at least in some cases ‑‑ by proposing that the central nervous system is so constituted that it gives positive feedback (enjoyment) to the animal as it attempts to realize a variety of potentials in a "field released from tension", to borrow Konrad Lorenz's jargon. It is precisely the independence from immediate demands of the environment that permits the trying out of so many skills in so many combinations. And thus it is that independence in action that needs to be encouraged by the response of the central nervous system.[15 play requires some intelligence] It is not difficult, then, to see the biological rationale for evolving such a mechanism.<span> </span>We humans call it play and do enjoy it.</p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">One of the characteristics of play is that it can be applied to a wide range of skills.<span> </span>In particular, it provides a very apt training regimen for developing those skills connected with intelligence, since they often have to do with indirect or postponed action. Intelligence has a role in social interaction, and thus there is a link to social play.<span> </span>But my concern at this time is with intelligence as a means of interacting with nature. And here is where the association with curiosity that Lorenz mentioned comes in.<span> </span></p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">Some animals which exhibit a great flexibility of response towards the environment ‑‑ "specialists in non‑specialization" ‑‑ also exhibit a great deal of curiosity.<span> </span>Such curiosity is typically present in a field released from tension, just as play is. In other words, curiosity is characterized by independence from the pressing demands of the environment; and it is, as far as we can tell, an enjoyable pursuit. Although it is clear that much play has nothing to do with curiosity, it is nonetheless plausible to think of curiosity as a form of play of a cognitive subject with its environment.<span> </span></p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">The object of the play, in this case, seems to be the development of the skills by which an individual can gain knowledge of its world.<span> </span>And it should be obvious that in developing such skills an individual actually does come to know its environment better. In species in which learning comes to an end when the individual is reasonably well adapted to a particular environment, those bits of knowledge obtained through the satisfaction of curiosity are of the greatest importance.<span> </span>In species whose individuals keep their mental flexibility for a good portion of their lives, the playful interaction with the environment is bound to continue.<span> </span>In humans, who sometimes tend toward what Poincare would have called "pure intelligence", that playful interaction may take on some very abstract forms.<span> </span></p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">Here is thus my account of the "delight" of science ‑‑an account rooted in our very nature.<span> </span>But this is an account that firmly links curiosity with our means of interacting with nature; and so presumably it links curiosity with what is useful.<span> </span>As I have argued, the product of our rehearsals in our exploratory relation with nature is the scientific views that we propose and sometimes believe.<span> </span>In the open‑ended environment that we face, however, we are unlikely to get a perfect conceptual adaptation the first time out.<span> </span>Fortunately, we do seem to be specialists in non‑ specialization: as long as social factors do not override our playful drives, as long as the field remains released from tension, we are quite able to come up with new combinations of intellectual and observational skills.<span> </span>And as our conceptual game with nature endures, so does our ability to adapt to a changing environment or to move into new niches.<span> </span>To the extent that science is a means for our intelligence to interact with the universe, the dynamic character of science is a consequence of our nature. And as our views change in accordance with that dynamic character, so changes the panorama of problems and opportunities that becomes available to our species. That is the final link that connects Poincare's delight with the practicality of science in the long run.<span> </span></p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">If the forces that motivate exploration are so connected with Poincare's delight, other aspects of exploration fall into place. An important reward of play comes when a new stage of performance arises from the combination and development of skills.<span> </span>When we find it we see it as the goal we had been groping for ‑‑ such is the feel of the perfectly kicked ball, of the graceful turn in the air, of the solution to a hard problem. If we have reason to believe that stage had never been reached before, we become aware of how far we have reached, and our sense of accomplishment is naturally so much greater.<span> </span>In attempting to satisfy our curiosity, the equivalent sense of accomplishment comes from being the first to find something that turns out to be important; and in the case of intellectual curiosity we may add the accomplishment of devising a view that can<span> </span>perform intellectually as no other did before.<span> </span>And thus the pursuit of the new combination, of the new vision, of the new land edges us on.<span> </span>It is the discovery of the new that constitutes the biggest prize.<span> </span>That is the sense of discovery implicit in play, and in the delight that accompanies it.</p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">We can now brush aside objections to the effect that scientists often work with no applications in mind, that they do not accept or reject scientific theories on any practical basis.<span> </span>For the scientists' lack of such awareness, or even unconscious intention, cannot detract from the practical value (we might say adaptive) of scientific curiosity anymore than it would in the case of the animals which are "specialists in non‑ specialization".<span> </span>Besides, it would be too simpleminded to expect that all scientific work should aim at dealing directly with the environment so as to get results from it.<span> </span>Much of that work is devoted to the mathematical, theoretical, and/or experimental articulation of scientific ideas (thus, in my view, it aims at dealing indirectly with the environment).<span> </span>And much other work attempts the integration of experience into a network that can then be applied (e.g. neo‑Darwinism). It is science as a whole, as our communal spectacles, that might be thought of as an instrument of adaptation.[16]</p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">We can also begin to understand in which sense nature inclines us toward exploration, so that by engaging in it we fulfill ourselves as human beings.<span> </span>Curiosity is imbued in us because it served our ancestors ‑‑ and ourselves ‑‑ well in allowing them to adapt to a variety of environments, in trying novel strategies to deal with any one given environment, and in coping with changing circumstances.<span> </span>That the satisfaction of curiosity is a form of play makes eminent sense given our complex nervous system.<span> </span>But that very system also makes us extremely complex animals, some might say more than mere animals.<span> </span>In exploration we do more than develop our sensory and motor skills, for our intellectual faculties, as we have seen, are precisely the sort most amenable to improvement by the indirect exercise of play. </p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">Furthermore, our potential is achieved only to the extent that our innate abilities develop to match the opportunities offered by the environments (social and physical) that we encounter.<span> </span>The ideal strategy for the fulfillment of our potential would thus include exposure to a variety of environments as well as the freedom to try out, combine, and refine our talents in them ‑‑ a freedom, that is, to play.<span> </span>In exploration, as a form of play aimed to satisfy our curiosity, both individually and collectively, we increase our mastery over nature while finding and developing in us those skills for which we are most suited. We have already seen that in rejecting or slowing down exploration we reject or slow down the refinement and possible replacement of the communal spectacles with which we perceive the universe.<span> </span>We have already discussed the deprivation that may result from that.<span> </span>But now we can go even further.<span> </span>For we have also seen that we by rejecting or slowing down exploration we hamper our own fulfillment as individual human beings and as human societies.<span> </span>This damage goes beyond the failure to achieve our intellectual and scientific potential.<span> </span>For just as our range for exploratory play is rich and complex, our systems of motivation and satisfaction ‑‑ our "feedback mechanisms"‑‑ are also rich and complex.<span> </span>In this case I would speculate that those systems would involve deep and sophisticated emotions. In the case of space exploration they would be associated, at the very least, with wonder, with excitement, with adventure.<span> </span>This is the heart of space exploration.</p> <p class="MsoNormal"> </p>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-56717069986439999392012-01-23T10:58:00.000-08:002012-01-23T11:01:05.449-08:00HUMAN NATURE AND THE NATURE OF SCIENCE I<p class="MsoNormal" style="line-height:12.0pt"><b>CHAPTER 11A</b></p> <p class="MsoNormal" style="line-height:12.0pt"><b> </b></p> <p class="MsoNormal" style="line-height:12.0pt"><b>HUMAN NATURE AND THE NATURE OF SCIENCE I<br /></b></p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">The account of science presented in Chapter 3 meets with an objection: my notion of a fundamental practicality of science goes against the grain of traditional philosophy of science.<span> </span>Philosophers have observed that scientific theories are seldom accepted or rejected on the basis of their practicality.<span> </span>They have also observed that scientists are more likely to be motivated by the search for truth or the satisfaction of their intellectual curiosity than by the good of mankind. This tradition is eloquently expressed in the words of another great French scientist and philosopher, Henri Poincare, who at the beginning of this century wrote that "the scientist does not study nature because it is useful; he studies it because he delights in it, and he delights in it because it is beautiful.<span> </span>If nature were not beautiful, it would not be worth knowing, and if nature were not worth knowing, life would not be worth living." [10] </p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">For Poincare the beauty that really counted was not that of "qualities and appearances" ‑‑ the beauty accessible to most human beings ‑‑ but rather that "profounder beauty which comes from the harmonious order of the parts, and which a pure intelligence can grasp."[11] That sentiment is not surprising in one who dedicated his life to understanding nature.<span> </span>But not all humans are so dedicated, and some of them have interests that would not coincide in the slightest with those of a mathematical physicist like Poincare.<span> </span>Nevertheless I think that Poincare was right in saying that scientists seldom study nature because it is useful.<span> </span>But I would stress a consequence, perhaps unintended, of his argument: that because life is worth living, nature is worth knowing. </p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">The reason is that there is a sense in which the satisfaction of scientific curiosity has something akin to adaptive value.<span> </span>To see this more clearly it is helpful to consider how the nature of science arises from the nature of man.<span> </span>And by the nature of man I have in mind that human beings are biological products of their universe, as much a part of that universe as trees and stars. Let me begin, then, by pointing out that curiosity has adaptive value in animals.<span> </span>Of course not all animals have curiosity, but those that do, say the Norway rat or the raven, can adapt to a great variety of environments or to a changing environment.<span> </span>Curiosity, most often in the spirit of play leads them to obtain knowledge of the environment in which they find themselves.<span> </span>Curiosity is thus the key to their flexibility ("specialists in non‑specialization," Konrad Lorenz called them), and their flexibility is the key to their adaptive success.[12]<span> </span>We must also remember that the structures that underlie intelligence are biological.<span> </span>As a result, Jean Piaget says that intelligence "...is the most highly developed form of mental adaptation, that is to say, the indispensable instrument for interaction between the subject and the universe when the scope of this interaction goes beyond immediate and momentary contacts to achieve far‑ reaching and stable relations."</p> <p class="MsoNormal" style="line-height:12.0pt"> </p> <p class="MsoNormal" style="line-height:12.0pt">In short, intelligence has adaptive value.<span> </span>But science is not only a product of intelligence:<span> </span>it is also a means by which intelligence conceives of the universe, as we have seen.<span> </span>In such a case, should not science be expected to have adaptive value as well?<span> </span>Many of the lines of argument developed in this chapter should testify in favor of this claim (e.g. the relation between theoretical achievement and realization of opportunity or of danger). It must be kept in mind, however, that not all our faculties were selected for their present uses.<span> </span>But there is no suggestion here that human brains were selected for atomic physics or to build space telescopes.<span> </span>The selective forces had long done their job before humans thought of atoms or rockets.<span> </span>Nonetheless this consideration does not prevent a faculty developed for something else to acquire adaptive value of its own.<span> </span>And in the case of science the connection is even closer than that, as I will discuss next time.</p> <p class="MsoNormal"> </p>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-38425117797932679282012-01-03T09:51:00.000-08:002012-01-03T09:54:00.401-08:00ACADEMICS<p class="MsoNormal"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">ACADEMICS</span></b></p> <p class="MsoNormal"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></b></p> <p class="MsoNormal"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">First let me wish you all a happy new year.<span> </span>To meet some requests, I have enclosed below a list of my own formal academic publications on the philosophy of space exploration.<span> </span>If you know of other academic publications in this new filed, please let me know.<span> </span>I will collect any such for a while and publish the list in a future posting.</span></b></p> <p class="MsoNormal"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></b></p> <p class="MsoNormal"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></b></p> <p class="MsoNormal"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">GONZALO MUNEVAR’S ACADEMIC PUBLICATIONS ON THE PHILOSOPHY OF SPACE EXPLORATION</span></b></p> <p class="MsoNormal"><b><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></b></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">"Report of an Interdisciplinary Course on Space Exploration," with John C. Kasher, in <i>Social Sciences and Space Exploration</i>, NASA Ep-192, 1984.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">"Rhetorical Grounds for Determining what is Fundamental Science: The Case of Space Exploration," in <i>Argument and Social Practice,</i> J.R. Cox, M.O. Sillars, and G.W. Walker, eds., Speech Communication Association, 1985, pp. 420-434.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">"Philosophy, Space Science and the Justification of Space Exploration," <i>Essays on Creativity and Science,</i> Diana M. DeLuca, ed. HCTE, Hawaii, 1986, pp. 89-96.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">"Pecking Orders and the Rhetoric of Science," <i>Explorations in Knowledge,</i> Vol. III, No. 2, Spring, 1986, pp. 43-48.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">"Space Colonies and the Philosophy of Space Exploration," <i>Space Colonization:<span> </span>Technology and the Liberal Arts,</i> C.H. Holbrow, A.M. Russell & G.F. Sutton, eds.,<i> American Institute of Physics, Conference Proceedings 148,</i> 1986, pp. 2-12.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif"" lang="ES-CO">"Filosofía y la Evaluación de la Tecnología Espacial," <i>Arbor,</i> May 1988, No. 509, Tomo CXXX, pp. 59-72.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif"" lang="ES-CO"> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">"Human and Extraterrestrial Science," <i>Explorations in Knowledge,</i> Vol. 6, No. 2, 1989, pp. 1-9.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">"Why Should Philosophy Influence Science Policy: The Case of Space Exploration," <i>Explorations in Knowledge,</i> vol. 13, No. 1, 1996, pp. 9-17.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">“Philosophy and the Exploration of the Solar System,” <i>Philosophic Exchange</i>, No. 28: 1997-1998, pp. 56-61. </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p> <p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Bookman Old Style","serif"">“A Philosopher Looks at Space Exploration,” as Chapter 13, Munevar G., <i>Evolution and the Naked Truth</i>, Ashgate, 1998, pp 169-179.<br /></span></p> <p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Bookman Old Style","serif""> </span></p> <p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Bookman Old Style","serif"">“SETI, Self-Reproducing Machines and Impossibility Proofs,” as Chapter 15, Munevar G., <i>Evolution and the Naked Truth</i>, Ashgatge, 1998, pp. 189-195. </span><span style="font-size:11.0pt;font-family:"Bookman Old Style","serif"" lang="ES-CO"></span></p> <p class="MsoNormal"><i><span style="font-size:12.0pt;font-family:"Times New Roman","serif"" lang="ES-CO"> </span></i></p> <p class="MsoNormal" style="text-autospace:ideograph-numeric ideograph-other"><span style="font-size:12.0pt;font-family:"Times New Roman","serif"" lang="ES-CO">“Venus y el Fin del Mundo,” <i>Eidos,</i> Vol. 4, March 2006, pp. 10-25.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif"" lang="ES-CO"> </span></p> <p style="text-align:justify;text-justify:inter-ideograph"><span style="font-size:11.0pt;font-family:"Bookman Old Style","serif"">“Humankind in Outer Space,” <i>The International Journal of Technology, Knowledge and Society</i>, Vol. 4, No. 5, 2008, pp. 17-25.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p> <p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Bookman Old Style","serif";color:black" lang="ES-CO">“Einstein y el límite de la velocidad de la luz,” in Guerrero G. (ed.) <i>Einstein: Científico y filósofo</i>, Programa Editorial Universidad del Valle, 2011, pp. 291-308.</span></p> <p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Bookman Old Style","serif"" lang="ES-CO"> </span></p> <p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Bookman Old Style","serif"" lang="ES-CO"><span> </span></span><span style="font-size:11.0pt;font-family:"Bookman Old Style","serif"">“Self-Reproducing Automata and the Impossibility of SETI.” Forthcoming in Geppert, A. (ed.) <i>Imagining Outer Space</i>, Palgrave Macmillan.</span></p> <p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Bookman Old Style","serif""> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Times New Roman","serif""> </span></p>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-36818630512960056142011-12-08T00:57:00.000-08:002011-12-08T00:58:51.184-08:00THE BALANCE OF NATURE<p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">CHAPTER 10B</span></b></p> <p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">THE BALANCE OF NATURE</span></b></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black">This is not to say that we are always looking out for the interests of the species, few of us are.<span> </span>But then we are practically never looking out for the interests of a stranger, although if we see him collapse on the street many of us would feel a strong impulse to come to his assistance. Similarly, the appropriate time to recognize the interests of the species is when we become aware that they are threatened.<span> </span>And in any event, insofar as we accept the responsibility of deciding for the species, the argument that ought to work is that which takes the interests of the species into account.<span> </span></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>I think that the social critics should be, on the whole, very well satisfied by now.<span> </span>But the ideological critics are a different matter altogether.<span> </span>They may agree, though grudgingly, that given the present situation space science provides a possible solution.<span> </span>Or even, that given the present dilemma, space science looks essential.<span> </span>Nevertheless, they may want to challenge the description of the dilemma and insist on a solution more to their liking.<span> </span>And their alternative is this. Space science looks imperative because of the enormous pressure that the incredibly large population is putting on the environment, particularly when that population demands increasingly larger per capita shares of energy and other resources.<span> </span>But is it not obvious that if our numbers were significantly reduced, and our demands for consumption lowered, then the pressure on the environment would be relieved?<span> </span></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Suppose that we institute programs that would lower the total population of the planet.<span> </span>First we cut it in half in fifty years.<span> </span>With other measures that would involve a simpler standard of living and reduced energy consumption per capita, this would certainly accomplish much to make our problems manageable.<span> </span>Suppose then that we continue to cut in half the population of the Earth every fifty years, until after a few centuries the impact of humans on the environment is no longer a threat to the entire planet.<span> </span>China is already taking stern measures to reduce its population drastically.<span> </span>It seems, then, that there are alternatives to the exploration of space.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Now, how could such a momentous decision to reduce population be implemented on a global scale? The amount of coercion in China is considerable, in spite of the fact that China is a relatively homogenous society in which a dominant political ideology facilitates near unanimity of opinion.<span> </span>But I am not sure it is reasonable to suppose that anything short of widespread and unmitigated disaster could bring together the different hostile factions in the world to put such a global program into effect.<span> </span>The disaster may come.<span> </span>Although by then it might be too late.<span> </span>And even if the struggle could still succeed, the misery visited upon mankind may be too high a price to pay, particularly if space exploration could have kept disaster at bay.<span> </span>It does not seem like much of an alternative after all.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>And what leverage would the Wendell Berrys of the world employ to launch the conflicting powers that be on a joint enterprise of such monstrous proportions?<span> </span>Surely not moral persuasion and enticements to instill what he calls good character.<span> </span>Appeals of that sort would not have a prayer, at least not in time to avoid the disaster which gives such views an air of reasonableness, however they may have to be accompanied by resignation. So it is unclear just how feasible this ideological alternative is, but two considerations would seem to buttress this position.<span> </span>The first is that we have to do something about the population growth anyway.<span> </span>Space exploration will not be in a position to play a significant role in the reduction of the Earth's population for a long time.<span> </span>If we could take a million people a year into space, which we cannot at the present, it would take thousands of years before we began to make a dent in the amount of population we have now, let alone on a population that is growing at today’s dangerous rate.<span> </span>We have centuries, at the most.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>The second consideration is that we better protect the Earth by nurturing respect toward it than by letting people think that we can always move onto another nest.<span> </span>For otherwise we imagine that spoiling our present nest is regrettable but not an insurmountable loss.<span> </span>Learning to live within the confines acceptable to our mother planet is a wiser policy because we already know that we can lead dignified and fruitful lives here. By contrast, learning to live in space is only a promise. Can we bet the future of mankind on it?<span> </span>The greatest gift we can make to posterity is a beautiful Earth and the strength of character to live in harmony with it.<span> </span>In other words, we accomplish more by preserving the natural balances that have been so accommodating to human beings in the past, and by restoring such balances where modern life has already disrupted them.<span> </span>The result of exercising greater moral responsibility toward the world is a better world.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Space exploration, on the other hand, presumably would continue the disruption of the natural balance.<span> </span>If technology has already caused a mess, why should we expect better?<span> </span>Moreover, space exploration would be worse than a necessary evil, for it is not an enterprise that we can engage in just once before returning to a more pastoral existence. As Berry says, in condemning the scientific mind, "(1) It would commit us to a policy of technological `progress' as a perpetual bargaining against `adverse effects.' (2) It would make us perpetually dependent on the `scientific' foretelling and control of such effects -- something that never has worked adequately, and that there is no good reason to believe ever will work adequately."<span> </span>Why could it not work?<span> </span>Because "when you overthrow the healthful balance of the relationships within a system --biological, political, or otherwise -- you start a ramifying sequence of problems...that is not subject to prediction, and that can be controlled only by the restoration of balance."<span> </span>Berry's warning is that "if we elect to live by such disruptions then we must resign ourselves to a life of desperate (and risky) solutions: the alternation of crisis and `breakthrough' described by E.F. Schumacher."<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#134124f6697c70b6__edn1" name="134124f6697c70b6__ednref1" title=""><span><span><span><span style="font-size:12.0pt;font-family:"Times New Roman","serif";color:black">[1]</span></span></span></span></a></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>How reasonable an alternative is this to the course of action I have recommended?<span> </span>The first thing that deserves comment is this matter of disruption and restoration of balance. A very early and rather important disruption of natural balance took place when life was born and changed the chemistry of the planet.<span> </span>Another crucial and massive disruption of balance came when the oxygen liberated by life "poisoned" the atmosphere and the oceans.<span> </span>And this was followed by the adaptation of life to oxygen, with the subsequent destruction of the cozy arrangements between early life and the environment.<span> </span>Disruptions of similar magnitude were brought about by the appearance of complex organisms, by the formation of an ozone layer, which made the land available to life --would it have been better for life to stay in the oceans? -- and then by the return of vertebrates to the water, which led to whales and dolphins. Ever since, the evolution of life has created new forms that have remade the environment anew, destroying the very memory of whatever balance had been struck previously, and leaving at best a few scattered fossils of what the Berrys of the time would have insisted on preserving.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>The fact of the matter is that life has often created new opportunities for itself, unwittingly no doubt, and has always changed the balance between its different forms --most of which are now extinct.<span> </span>The biota of the planet has remade itself many times over.<span> </span>The natural balance of the ideological critics is merely a fiction, a temporary arrangement that would change even if there were no human beings around to mess things up.<span> </span>And surely life does not exhaust the range of natural causes that have brought about massive disruptions of balance.<span> </span>Do volcanic eruptions, droughts, and asteroids always make for small reversible changes?<span> </span>What may we say, incidentally, of the galactic disruption that forced the collapse of the pre-solar cloud into a planetary system? Of the earlier obliteration of what may have looked like states of cosmic equilibrium, and thus of natural balance?<span> </span>Which balance is it that we are morally obliged to restore?</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Clearly humans are not the only creatures that transform their environment and interfere with it.<span> </span>R.C. Lewontin, S. Rose, and L.J. Kamin point out that "all living beings both destroy and create the resources of their own continued life.<span> </span>As plants grow, their roots alter the soil chemically and physically.<span> </span>The growth of white pines creates an environment that makes it impossible for a new generation of pine seedlings to grow up, so hardwoods replace them.<span> </span>Animals consume the available food and foul the land and water with their excreta.<span> </span>But some plants fix nitrogen, providing their own resources; people farm; and beavers build dams to create their own habitat."<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#134124f6697c70b6__edn2" name="134124f6697c70b6__ednref2" title=""><span><span><span><span style="font-size:12.0pt;font-family:"Times New Roman","serif";color:black">[2]</span></span></span></span></a></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>The issue is not, then, one of disrupting balance and interfering with the environment. Perfect balance can be found only right before the birth of the universe and perhaps right after its death. Even then we do not really know.<span> </span>And to avoid interfering with nature would be out of character for living things, while impossible to achieve anyway.<span> </span>The issue is rather one of interfering wisely, and of preserving (approximately) certain balances that offer the best compromises for a worthwhile existence on this planet. But how are we going to achieve these goals without the kind of global and long-term knowledge that we have discussed in this book?</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>To say that we should diminish the presence of man--in numbers and in scope of action--so that nature may run its course as undisturbed as possible, assumes that man is a scourge upon the land, and it denies man the very liberties we give to the rest of living things. But even so, how far should that diminution go?<span> </span>And at what price in human misery?<span> </span>I think that this attitude, to force man back, also assumes that there can be no middle ground between the obliteration of the environment and the reduction of man to insignificance.<span> </span>For at any place in the middle we will see a rather large human interaction with the environment.<span> </span>We are sinners, it appears, and now the time has come to pay for our sins. Without this general mea culpa in the hearts of the large majority of human beings, it is difficult to see why they should act in what surely will seem to many as directly against their interests and those of their descendants.<span> </span>Should we not instead gain knowledge of the world in order to determine what is wise?<span> </span>No.<span> </span>These critics would rather do penance than science.<span> </span></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Nevertheless, as long as our dealings with nature involve a creative element, as long as the transformation of the environment is inevitable, with or without our participation, it seems more sensible to learn the secrets of nature so we can act with our eyes open.<span> </span>Berry and his cohorts may not think highly of many of the opportunities that space exploration may open to us.<span> </span>But why should they bar others from taking advantage of them?<span> </span>What right do they have to decide for others what good character is and to insure that nothing else will have greater priority?<span> </span>Their case is based on a myth about nature.<span> </span>And that is only half the trouble.<span> </span></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>The present rate of population growth may well be unsustainable, and for space exploration to make a difference it would have to provide means of carrying billions of people into space, a feat that is not in the cards in the foreseeable future, although eventually it will.<span> </span>In the meantime, space science may help us monitor the pressure on the environment and avail our planet of the resources of the solar system.<span> </span>Moreover, let us remember that in the long run the workings of nature, if man does nothing about them, are bound to create first a most unpleasant world for our descendants and then bring extinction upon them.<span> </span>Having science is no guarantee that those things will not happen.<span> </span>We cannot be assured that the desired level of knowledge is possible within whatever time limits infringe on our future.<span> </span>Nor can we be certain that just because we have that knowledge we will choose according to the best interests of the species.<span> </span>But we can be sure that, without the global knowledge that requires space science, we will simply have no choice to make. Our descendants will suffer for it; and eventually our species will disappear at the earliest cosmic inconvenience.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>A species full of self-hatred may well choose such a path.<span> </span>But is the appeal of presumed atonement the most fitting choice for us to make?<span> </span>That ascetic choice may buy us a bit of time, but for what?<span> </span>In the long run it leads us straight into a grave.<span> </span>The other choice, the one that really lets nature run its course offers the opportunities for expansion and diversification that so far life has been fortunate to procure for itself. I refer to it as the one that really lets nature run its course because it recognizes that we, too, are part of nature. There is no question in my mind that in this case the way of nature has the potential for greater wisdom.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Sometimes it is said that a little bit of knowledge is dangerous, and that since we are not likely to have complete knowledge through space or any other kind of exploration, we are better off not embarking on this scientific enterprise in the first place.<span> </span>But we have seen, clearly I hope, that even though a bit of knowledge can be dangerous, there is no long future in ignorance.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>My point is not that environmental concerns are unimportant.<span> </span>Just the opposite.<span> </span>They are very important and we should take the steps necessary to make decisions based on the most comprehensive picture of the Earth's environment we can obtain.<span> </span>Only then we can pay proper attention to the interests of our species.<span> </span>What I argue against is the rigid demand to act on myths about nature that have little more than mysticism in their favor.</span></p> <p><span style="color:black"><span> </span>The decision is, of course, not mine to make.<span> </span>My intent has been to bring before the reader the considerations relevant to these large issues and the arguments that are most suitable to them.<span> </span>I hope I have shown that the very heart of space exploration contains within it the best justification of the entire enterprise.<span> </span>In doing my small part to reduce the dimming of starlight, I trust that, as H. G. Wells said, “</span>Life, for ever dying to be born afresh, for ever young and eager, will presently stand upon this earth as upon a footstool, and stretch out its realm amidst the stars.”<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#134124f6697c70b6__edn3" name="134124f6697c70b6__ednref3" title=""><span><span><span><span style="font-size:12.0pt;font-family:"Times New Roman","serif"">[3]</span></span></span></span></a></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"> </span></p> <p class="MsoNormal"> </p> <br /> <hr align="left" size="1" width="33%"> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#134124f6697c70b6__ednref1" name="134124f6697c70b6__edn1" title=""><span><span><span><span style="font-size:10.0pt;font-family:"Times New Roman","serif"">[1]</span></span></span></span></a> Op. cit., p. 83.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#134124f6697c70b6__ednref2" name="134124f6697c70b6__edn2" title=""><span><span><span><span style="font-size:10.0pt;font-family:"Times New Roman","serif"">[2]</span></span></span></span></a> Lewontin, R.C., S. Rose, and L. J. Kamin. <i>Not in Our Genes: Biology, Ideology, and Human Nature</i> (New York: Pantheon Books, 1984).</p> </div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#134124f6697c70b6__ednref3" name="134124f6697c70b6__edn3" title=""><span><span style="font-size:10.0pt"><span><span><span style="font-size:10.0pt;font-family:"Times New Roman","serif"">[3]</span></span></span></span></span></a><span style="font-size:10.0pt"> H. G. Wells,<i> The Outline of History, </i>1920, from <cite><a href="http://www.spacequotes.com/" target="_blank">www.spacequotes.com/</a>.</cite></span></p> <p> </p>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com1tag:blogger.com,1999:blog-5232161716029893381.post-27904957334763981752011-11-27T00:28:00.000-08:002011-11-27T00:32:50.514-08:00Chapter 10A Again<div id=":8m" class="ii gt"><div id=":8n"> <p class="MsoNormal"><span style="font-size: 12pt; color: black;">I was unhappy with my previous posting, and so I decided to rewrite it and add to it the material I had planned to post today.<br /></span></p><p class="MsoNormal"><span style="font-size: 12pt; color: black;"><br /></span></p><p class="MsoNormal"><span style="font-size:12.0pt;color:black">CHAPTER 10A</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black">THE VALUE OF HUMAN SURVIVAL</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black">H.G. Wells said once that our choice is the universe or nothing.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__edn1" name="133e3fd832cb1bcf__ednref1" title=""><span><span><span><span style="font-size:12.0pt;font-family:"Times New Roman","serif";color:black">[1]</span></span></span></span></a> And if the argument of this book is sound, he was not that far off the mark.<span> </span>The way humans look at the world, the way they interact with the world, gives them a panorama of problems and opportunities that will change as they strive to satisfy their curiosity: a dynamic science leads to a constantly evolving panorama.<span> </span>To grow is to adapt to a changing environment or to a variety of environments.<span> </span>Given the long-term prospects of the human species, to grow scientifically, into the cosmos, is to hedge our bets against extinction.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Two important questions come to mind at this stage.<span> </span>The first is: why should survival be a value? In particular, why should human survival be a value?<span> </span>If we justify space exploration by reference to survival and to the material improvement of human life, the social critics should be satisfied.<span> </span>Their objectives, in the long run, require that we go into space. But some of the ideological critics may prove more ornery.<span> </span>Thus Wendell Berry supposes that the abundance of resources in space will produce bad character, for good character requires the discipline of finitude.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__edn2" name="133e3fd832cb1bcf__ednref2" title=""><span><span><span><span style="font-size:12.0pt;font-family:"Times New Roman","serif";color:black">[2]</span></span></span></span></a></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>That the survival of the human species is a value may seem beyond question to most of us, although there might be some who prefer extinction to bad character (not that I wish to suggest here that Berry would go that far) or to decreased chances of spiritual salvation.<span> </span>But even overwhelming agreement on the value of survival might not satisfy some thinkers in their more philosophical moments.<span> </span>It seems that we value survival very highly, they might say, but why should we so keen on leaving behind imperfect creatures much like ourselves?</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>In such philosophical moments, questioning a value is normally taken as a demand to identify some other, more basic value from which the first one is derived.<span> </span>This is similar to how we presumably justify actions: "This is the right action because it will bring about X and X is a good thing."<span> </span>But the more basic value (or good thing) that does the justifying can itself be questioned, so we then look for an even more basic value (or good thing) until eventually we arrive at a good thing that is not merely good but good in itself, that is, whose goodness does not depend on anything but its own nature. <span> </span>Why do we work?<span> </span>Because we get paid? <span> </span>Why is money a good thing? Because we can use to buy food and clothes, pay the rent, etc. <span> </span>Why do we want to do those things?<span> </span>Because they make us happy. <span> </span>And in happiness, Aristotle thought, we find an end that is complete and self-sufficient.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__edn3" name="133e3fd832cb1bcf__ednref3" title=""><span><span><span><span style="font-size:12.0pt;font-family:"Times New Roman","serif";color:black">[3]</span></span></span></span></a><span> </span>The question “why do we want to be happy” makes no sense. <span> </span>Aristotle had in mind not transient happiness, but a happy life as a whole. <span> </span>He also thought it was obvious that the happiness of a society was of greater value than the happiness of a single individual. <span> </span>Of course, there seems to be a clear connection between human happiness and human survival.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Since this approach grounds ethical justification on a human value, human happiness, some may object that it is therefore relative to our own species. <span> </span>This objection seems to underpin the notion that we should not prefer the good of our own species to that of other living things in our planet, or even to the rocks of another planet.<span> </span>Oftentimes the objection is expressed as the view that ethics and other disciplines of value are "objective" only insofar as their laws are eternal and universal. <span> </span>As characterized by Peter Singer, who criticizes it, the view claims that "The laws of Ethics...existed before there was life on our planet and will continue to exist when the sun has ceased to warm the earth."<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__edn4" name="133e3fd832cb1bcf__ednref4" title=""><span><span><span><span style="font-size:12.0pt;font-family:"Times New Roman","serif";color:black">[4]</span></span></span></span></a> <span> </span>Moreover, eternal (absolute) laws of ethics seem to demand eternal (absolute) values.<span> </span>Thus a relative value such a human happiness (or human survival) cannot provide an adequate justification for our actions.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Absolute values, however, are not all they are cracked up to be. <span> </span>Conflict may arise between two or more absolute values. <span> </span>Or an absolute value may be of small significance in a particular context and thus should yield to relative values. <span> </span>Besides, absolute laws could in principle be derived from values that always depend on context or on subjective preference, i.e. relative.<span> </span>For example, consider utilitarianism (i.e., roughly, the view that the balance of good vs. bad consequences of an action--its utility--determine its rightness, given the utilities of the alternative actions).<span> </span>At least one version of utilitarianism would calculate utility in accordance with the values assigned by the individuals who would enjoy or suffer the consequences of the action being contemplated.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__edn5" name="133e3fd832cb1bcf__ednref5" title=""><span><span><span><span style="font-size:12.0pt;font-family:"Times New Roman","serif";color:black">[5]</span></span></span></span></a></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>I need not show that human survival is an absolute value, or that there must be an absolute law of ethics that gives survival a very high priority.<span> </span>I appeal to it in order to show that space exploration is in the interest of the species.<span> </span>When I point out that space exploration can save us from the dangers posed by asteroids and the sun’s becoming a red giant, I give a strong reason to pursue it.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>A reason in matters of prudence, or of ethics, need not be one that appeals to an absolute ground of any kind.<span> </span>A reason must be a reason for action, and so it must be aimed to convince the intended audience.<span> </span>This is not to say that efficacy alone is sufficient to commend reasons.<span> </span>The fallacious reasoning of much advertisement may well appeal to the masses of the unwary but would be exposed to ridicule in less superficial disputes.<span> </span>In some polemics the stakes and the standards may be very high.<span> </span>This need not mean that some ideal is approached but that greater care must be exercised to take into account the sorts of considerations that may be brought up by all the parties concerned. And greater care must be exercised not because some of those parties are in possession of truly higher standards of reason or have a more direct line to the truth – they might or might not – but precisely because we have more perspectives in play, because their diversity demands a sharper, more comprehensive case if their potential objections are to be met.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>To give ethical reasons to someone is then to give him reasons that take his concerns and interests into account.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__edn6" name="133e3fd832cb1bcf__ednref6" title=""><span><span><span><span style="font-size:12.0pt;font-family:"Times New Roman","serif";color:black">[6]</span></span></span></span></a> In discussion with members of another society, we can hardly make way with claims to the effect that our customs are better than theirs because ours are ours, or because our customs appeal to us.<span> </span>A convincing argument would have to show them that, in some respect that they may come to see as important, our customs work better for us than theirs do for them. Or if what we really want is for them to adopt ours, we must show them that our customs will work better for them, too. If action is the intended goal of reason in matters of prudence and ethics, how can reason succeed if it cannot appeal to the audience?<span> </span>And what appeal can there be where the aims, desires, and interests of the audience are ignored?</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>In an important respect this view preserves an element of universality, although not the peculiar ground of objectivity of so many views in ethics.<span> </span>As the Oxford philosopher J.L. Mackie put it: "If there were objective values, then they would be entities of a very strange sort, utterly different from anything else in the universe.<span> </span>Correspondingly, if we were aware of them, it would have to be by some special faculty of moral perception or intuition, utterly different from our ordinary ways of knowing everything else."<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__edn7" name="133e3fd832cb1bcf__ednref7" title=""><span><span><span><span style="font-size:12.0pt;font-family:"Times New Roman","serif";color:black">[7]</span></span></span></span></a><span> </span>No.<span> </span>The element of universality depends rather on the realization that, as Singer says, "… one's own interests are one among many sets of interests, no more important than the similar interests of others."<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__edn8" name="133e3fd832cb1bcf__ednref8" title=""><span><span><span><span style="font-size:12.0pt;font-family:"Times New Roman","serif";color:black">[8]</span></span></span></span></a> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Where the only relevant difference between my wish and yours is that it is mine, I am generally not in a position to give you reasons why you should behave as I want you to.<span> </span>An intelligent being should presumably be able to detect what the relevant factors in a dispute are, and discard those that are revealed as arbitrary.<span> </span>Or else he would go ahead with the full knowledge that his case is also arbitrary and that he has no rational claim upon the behavior of those he was trying to persuade.<span> </span>Practical reasoning that will not treat impartially the interests of all parties will not succeed: It cannot motivate action.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>These considerations lead Singer to conclude that all rational beings should come to this process of reasoning.<span> </span>If so, this reasoning would have an eternal and universal aspect. For according to Singer, "Wherever there are rational, social beings, whether on earth on in some remote galaxy, we could expect their standards of conduct to tend toward impartiality, as ours have."<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__edn9" name="133e3fd832cb1bcf__ednref9" title=""><span><span><span><span style="font-size:12.0pt;font-family:"Times New Roman","serif";color:black">[9]</span></span></span></span></a><span> </span>This is not to say that all rational beings would adhere to the same specific norms of conduct, for those specific norms may have developed to meet entirely divergent constraints on behavior, as we already saw in Chapter 8.<span> </span>Nor is it to say that ethical behavior between all intelligent species is possible, since such behavior requires a possible commonality of interests that may not always be there (such commonality need not be of prior interests, since in new circumstances complex intelligent beings are capable of developing new interests; although there is no guarantee that new, appropriate interests will in fact be developed). </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>In this manner we can explain why the appeal to values is thought to provide reasons, for values themselves, as Singer points out, are inherently practical.<span> </span>"To value something," he says, "is to regard oneself as having a reason for promoting it.<span> </span>How can there be something in the universe, existing entirely independently of us and our aims, desires, and interests, which provides us with reasons for acting in certain ways?"<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__edn10" name="133e3fd832cb1bcf__ednref10" title=""><span><span><span><span style="font-size:12.0pt;font-family:"Times New Roman","serif";color:black">[10]</span></span></span></span></a> When I point out the connections between space science and survival, I consciously expect that my case will be successful because it does take into account what I believe are the aims, desires, and interests of my intended audience.<span> </span>I assume that most normal human beings care deeply about the consequences that I have outlined.<span> </span>Indeed, since what I am doing is trying to meet the objections of the critics, I ought to be on firm ground, for they very explicitly announce their concern for the welfare of all humankind (at least in the case of the social critics).</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Should humans be interested in their own interests?<span> </span>The question does not even deserve to be called rhetorical.<span> </span>What often happens, though, is that reasons that presumably take our interests into account may be challenged on the grounds that they really do not -- that if we consider other relevant factors, or a long view of things, then we realize that what appeared to be in our interest really is not.<span> </span>But how can it be that survival is not really in our best interest?</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>There are cases where survival clearly does not override other reasons (or motives) for action, and where we may agree that it should not.<span> </span>Cases, for example, in which someone risks his life to save his child's, or a stranger's for that matter.<span> </span>Or cases in which principle takes precedence.<span> </span>But all these are cases worthy of admiration precisely because we recognize that the person's survival was in his best interest, but that he disregarded it for the benefit of a higher purpose.<span> </span></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Moreover, I would venture to guess that the reason we are willing to let personal survival be overridden is that this higher purpose is somehow involved with making life better for those that remain, or even to make sure that others do remain. As this purpose expands in scope, it will ultimately cover the well-being of all mankind.<span> </span>And here we should not speak merely of mankind as we may find it in a slice of history, but mankind as it extends through history into the future.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Religion sometimes demands the sacrifice of lives for rather obscure goals, or for goals that only the faithful find less than revolting.<span> </span>And political passion is often guilty of similar motivations.<span> </span>But it is difficult to see how a religion or a political ideology that demanded, or permitted, the destruction of the entire human species, that would deny the future a chance, could justify itself to the most general of audiences. Even so I am not inclined to say that no conceivable set of circumstances could provide a reason more pertinent than the survival of mankind.<span> </span>Still, such a strict requirement is not necessary.<span> </span>I presume to have given good, convincing reasons.<span> </span>Unless someone offers stronger alternatives, I would like to think that I have done enough in this respect.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>The previous point is that the line of argument that culminates with a connection<span> </span>to our survival and the betterment of our material condition need not go to a deeper level of justification. This point was clearly aimed at a philosophical critic who might question the ground of justification I provide for the exploration of space. Nevertheless I have not yet earned the right to bring the discussion to an end.<span> </span>First of all other critics may wonder about the appeal to the interests of humanity, not because appealing to interests is not enough but because they may think that "humanity" is too elusive a subject to have interests.<span> </span>And second, some of the ideological critics may resist the conclusion that space science is necessary for the long-term survival of the human species.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>The first objection is less powerful than one may imagine. <span> </span>Of course, our species is not some kind of super-organism of which individual human beings are the cells.<span> </span>There is surely no talking to any such "humanity". Humanity in a clear sense does not think what is best for it, nor does it recognize its interests, simply because there is no conscious subject there to think or recognize.<span> </span>Individual human beings do the thinking and recognizing.<span> </span>That is fair enough.<span> </span>Moreover, the interests of human beings are individual interests, what do they have to do with the interests of humans who may live several million years hence?<span> </span>How compelling can that appeal to the future be?<span> </span>How compelling should it be?</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>I would like to offer two responses, one rhetorical and the other philosophical.<span> </span>The rhetorical response is this.<span> </span>If my aim is to meet the objections against space exploration by the social and ideological critics, this particular point can do little against my case.<span> </span>For those objections cannot even get off the ground unless we assume first that it is not only possible but also our duty to do what is best for humanity.<span> </span>That is, we recognize that we should act not only so as to ensure our own well being but that of others.<span> </span>The audience, in a figurative but still important respect, are the people of the Earth.<span> </span>If that were not so, what would be the point of arguing that combating poverty is more important than observing the X-ray emissions from the vicinity of possible black holes?<span> </span>Or of suggesting that science is not wise because in the long run it will bring us to grief?<span> </span>The "us" here are surely not those of us who may hear the warning when first issued, but those in posterity whose world we may swindle by our recklessness of today.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>And now we can move from the purely rhetorical to more general or philosophical remarks.<span> </span>The reason the objections of the social and ideological critics do have a leg to stand on, although they turn out to be ultimately mistaken, is that as a matter of fact we do decide for posterity to a great extent.<span> </span>We may plant the trees from which “our” descendents will receive nourishment and shade, or we may destroy what could have given them a fighting chance against drought and famine.<span> </span>It is for them to make their own decisions, but at least the initial situation in which they will find themselves is more of our making than of theirs. Nor should we think that a society is merely an aggregate of individuals, and the species an aggregate of societies.<span> </span>Even if there is no super-organism, the whole does amount to more than the sum of its parts.<span> </span>Society is not a mere statistical distribution of individual properties.<span> </span>An individual that belongs to a society has characteristics that he could not have by himself.<span> </span>An advanced scientific and literary society, for example, builds libraries, universities, and laboratories, which enable an individual to educate himself for a style of life that would not exist without those institutions.<span> </span>The choices and opportunities open to him are not those that we could have without the benefit of the past efforts of generations that brought about the world into which he was born. No one could choose to be a modern farmer without the technology this century has provided, simply because the things a modern farmer does would not be possible otherwise. Nor could one choose to be a goalie in a soccer team if the game did not exist. In a primitive society it is very difficult to become a scientist, or a movie actor, or for that matter an effective critic of technology, since he will have little acquaintance with it.<span> </span>And in some societies dominated by religion, the female half of the population do not have the right to drive a car, receive an education, or even show their faces.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>What we are, what we may become obviously depends on our own efforts and talents.<span> </span>But it also depends on the range of choices, on the freedoms, and on the starting points that our society and culture make available to us.<span> </span>We do not become ourselves in a vacuum.<span> </span>But we also change the society by our choices, and thus we change the face of posterity, and sometimes its very substance. Some may wish to deny that our dialectical relationship with society imposes on us obligations of gratitude. <span> </span>But with a bit of attention, even they should realize that the present generation does decide for mankind, whether unwittingly or not.<span> </span>And they should realize also that the choices we face today are particularly important, more so perhaps than the choices most other generations of humans had to make. Nor is my case aimed strictly to the present generation.<span> </span>Now that space exploration has become a feasible alternative, these controversies have only been born.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Survival of the species is not a value just because it is in accordance with evolution.<span> </span>In the first place survival is not the goal of evolution.<span> </span>Evolution has no goals.<span> </span>And besides that, most species that ever lived are now extinct. Survival is a value to us because without it all the other interests of the species may become moot.<span> </span>And even though the interests of many individuals do not depend on the survival of the species, their collective actions often affect the species as a whole-- and when they recognize this, they care how it all comes out in the wash.<span> </span></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>According to some important contemporary views influenced by biology, it is in the nature of human beings to care about the fate of their descendants.<span> </span>This tendency can be explained by the comparative study of life forms and their drive to insure that their genes remain in the world even after they themselves are gone, and especially by the mechanism of kin selection and its concomitant kin altruism.<span> </span>But even if some are suspicious of such sociobiological studies and would rather speak in terms of culture, it would be difficult to deny that survival is in the interest of the species, or that our actions today may affect that interest tomorrow. <span> </span>Knowing that, it is a pretense to argue, as some fanciful philosophers do, that since future generations are not yet born, they do not have rights (for they are not “real”), and therefore we cannot be said to have obligations towards them.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__edn11" name="133e3fd832cb1bcf__ednref11" title=""><span><span><span><span style="font-size:12.0pt;font-family:"Times New Roman","serif";color:black">[11]</span></span></span></span></a><span> </span>Were they correct, I could not be accused of mass murder if I were to leave a large bomb hidden under the floor of the newborn wing of a hospital, timed to go off in six months, since none of my future victims would have been born by the time I hid the bomb.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__edn12" name="133e3fd832cb1bcf__ednref12" title=""><span><span><span><span style="font-size:12.0pt;font-family:"Times New Roman","serif";color:black">[12]</span></span></span></span></a> <span> </span>Nor can I leave the bomb there even if I did not plant it myself. <span> </span>Thus we do have obligations to ensure that CFCs no longer destroy the ozone layer so that our grandchildren will not suffer in large numbers from skin cancer. <span> </span>And we also have a positive obligation to put in place space systems to warn us of asteroid impacts and to deflect them, lest our descendants go the way of the dinosaurs.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>This is not to say that we are always looking out for the interests of the species, few of us are.<span> </span>But then we are practically never looking out for the interests of a stranger, although if we see him collapse on the street many of us would feel a strong impulse to come to his assistance. Similarly, the appropriate time to recognize the interests of the species is when we become aware that they are threatened.<span> </span>And in any event, insofar as we accept the responsibility of deciding for the species, the argument that ought to work is that which takes the interests of the species into account.<span> </span></span></p> <p class="MsoNormal"> </p> <div><br /> <hr align="left" size="1" width="33%"> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__ednref1" name="133e3fd832cb1bcf__edn1" title=""><span><span><span><span style="font-size:10.0pt;font-family:"Times New Roman","serif"">[1]</span></span></span></span></a> Taken from Carl Sagan in <a href="http://www.imdb.com/title/tt0081846/quotes?qt=qt0317500" target="_blank">http://www.imdb.com/title/<wbr>tt0081846/quotes?qt=qt0317500</a>.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__ednref2" name="133e3fd832cb1bcf__edn2" title=""><span><span><span><span style="font-size:10.0pt;font-family:"Times New Roman","serif"">[2]</span></span></span></span></a> See Berry’s contributions to <i>Space Colonies</i>, ed. by Stewart Brand (New York: Penguin Books, 1977), pp. 36-37 and 82-85.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__ednref3" name="133e3fd832cb1bcf__edn3" title=""><span><span><span><span style="font-size:10.0pt;font-family:"Times New Roman","serif"">[3]</span></span></span></span></a> Aristotle, <i>Nicomachean Ethics</i>, Bk. 1, Ch. 7, 2<sup>nd</sup> Edition, translated by Terence Irwin (Indianapolis: Hackett Publishing Company, 2000).</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__ednref4" name="133e3fd832cb1bcf__edn4" title=""><span><span><span><span style="font-size:10.0pt;font-family:"Times New Roman","serif"">[4]</span></span></span></span></a> Peter Singer, <i>The Expanding Circle: Ethics and Sociobiology</i> (New York: Farrar, Strauss and Giroux, 1981), p. 105.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__ednref5" name="133e3fd832cb1bcf__edn5" title=""><span><span><span><span style="font-size:10.0pt;font-family:"Times New Roman","serif"">[5]</span></span></span></span></a> Many utilitarians, however, assign to pain and pleasure absolute values, positive or negative respectively.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__ednref6" name="133e3fd832cb1bcf__edn6" title=""><span><span><span><span style="font-size:10.0pt;font-family:"Times New Roman","serif"">[6]</span></span></span></span></a> In this I follow Singer in his <i>The Expanding Circle</i>, op. cit.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__ednref7" name="133e3fd832cb1bcf__edn7" title=""><span><span><span><span style="font-size:10.0pt;font-family:"Times New Roman","serif"">[7]</span></span></span></span></a> Quoted in Singer, ibid., p. 107.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__ednref8" name="133e3fd832cb1bcf__edn8" title=""><span><span><span><span style="font-size:10.0pt;font-family:"Times New Roman","serif"">[8]</span></span></span></span></a> Ibid., p. 106.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__ednref9" name="133e3fd832cb1bcf__edn9" title=""><span><span><span><span style="font-size:10.0pt;font-family:"Times New Roman","serif"">[9]</span></span></span></span></a> Ibid.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__ednref10" name="133e3fd832cb1bcf__edn10" title=""><span><span><span><span style="font-size:10.0pt;font-family:"Times New Roman","serif"">[10]</span></span></span></span></a> Ibid., 107.</p> </div> <div> <p class="MsoNormal" style="text-autospace:none"><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__ednref11" name="133e3fd832cb1bcf__edn11" title=""><span><span><span><span style="font-size:10.0pt;font-family:"Times New Roman","serif"">[11]</span></span></span></span></a> Robert M. Adams, "Existence, Self-Interest, and the Problem of Evil," <i>Nous</i> I3 (1979): 57. Derek Parfit, "On Doing the Best for Our Children," in <i>Ethics and Population</i>, ed. Michael Bayles (Cambridge, MA: Schenkman, I976), pp. 100-102. Thomas Schwartz, "Obligations to Posterity," in <i>Obligations to Future Generations</i>, ed. Richard Sikora and Brian Barry (Philadelphia: Temple <span>University Press, I978). <span> </span>For a discussion see</span><span> Robert Elliot, “The Rights of Future People,” <i>Journal of Applied Philosophy </i>6, no. 2 (1989): 159–69.</span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#133e3fd832cb1bcf__ednref12" name="133e3fd832cb1bcf__edn12" title=""><span><span><span><span style="font-size:10.0pt;font-family:"Times New Roman","serif"">[12]</span></span></span></span></a> Presuming that I time it so precisely that no nurses or visitors will be killed.</p> </div> </div> </div></div>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-12442275986555399402011-11-02T23:03:00.000-07:002011-11-02T23:05:14.856-07:00Apologetics?<div id=":8o" class="ii gt"><div id=":8p"> <p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">Chapter 9D</span></b></p> <p class="MsoNormal"><b><span style="font-size:12.0pt;color:black"> </span></b></p> <p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">Apologetics?</span></b></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black">By now some readers may feel that this apology of space technology is turning into the confessions of Pollyanna.<span> </span>If space has done much to drive technology, in some way it must have also influenced the development of the armaments that have held the world hostage to nuclear terror.<span> </span>However diffuse, that influence must have been there.<span> </span>But the most important point is this.<span> </span>If it had not been for technology we would not have been in a position to destroy life on Earth.<span> </span>Once you achieve a certain degree of technological proficiency, total destruction becomes a real possibility.<span> </span>Since space will increase our technological proficiency even more, the military will have even more means of threatening the welfare of human beings.<span> </span>And one day something may go wrong . . . .<span> </span>Moreover, this relationship between the military and technology is inevitable because the military has the function of amassing the best arsenals that it can get its hands on.<span> </span>Thus the military will always try to put technology to its own uses. Some may also fear that further advances in technology may place nuclear weapons within the reach of fanatics and terrorists.<span> </span>The fire that we received from the gods has been fanned by our aggression and our ambition.<span> </span>It may yet reduce us to ashes.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Nevertheless, this line of argument cannot be accepted on <i>a priori</i> grounds alone.<span> </span>And as we have seen, the perceptions that give it plausibility do not square clearly with an examination of the historical developments.<span> </span>In any event, we should be weary of endowing this presumed inevitability of the connection between science and destruction, via technology, with the full status of a law of history.<span> </span>In the first place, the existence of laws of history is at best a debatable philosophical thesis.<span> </span>In the second place, this particular "law" seems to be underwritten by some rather unclear beliefs about aggression and human nature.<span> </span>Whether humans are aggressive by nature still is an open question.<span> </span>Even if Rousseau said that men are perverse and learning only makes them worse, our understanding of human aggression is not yet at the stage where we can use it to declare laws of history. </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>But let me set aside these rather abstract considerations. Consider instead that not all possible technologies become reality.<span> </span>No one may think of some of them, for example.<span> </span>And even most technologies that people contemplate never are attempted.<span> </span>Of course the military has a lot of money and influence.<span> </span>Nonetheless, that is not enough reason to conclude that our anxious predicament was inevitable.<span> </span>Many unfortunate coincidences were required.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Although the atomic bomb was theoretically possible, it demanded an extraordinary commitment of scientific talent and military funds.<span> </span>If it had not been for the threat that Hitler might be developing such a bomb, it is difficult to see why the American scientists would have been so willing to work on the project or why the Army would have thought seriously of embarking on such a quest.<span> </span>And the step from atomic to hydrogen bomb also required a major effort that could be justified only by the paranoia of the Cold War. But the world could have been very different.<span> </span>Hitler could have been killed early.<span> </span>Or he might have won.<span> </span>The Cold War could have degenerated into full confrontation, and one of the superpowers might have established hegemony over the entire world -- a new grand Roman Empire.<span> </span>None of the technological feats in question came easy.<span> </span>A slightly different timing of events would have changed the political and economic environment that permitted them to be born and prosper.<span> </span>The use of liquid-fuel rockets as weapons is a case in point.<span> </span>If Oberth had listened to the advice of his teachers, his book would not have changed von Braun's life -- it would not have turned him into the VFR's able envoy to the German army.<span> </span>Space rockets might have thus never become ICBMs.<span> </span></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Is it not reasonable to suppose that eventually those weapons would have been built anyway?<span> </span>In some historical scenarios, yes.<span> </span>In others, not.<span> </span>A person does not always buy a rifle whether he needs it or not, just for the hell of it.<span> </span>It depends on what else seems important at the time.<span> </span>But could space technology have been developed in a different world?<span> </span>And if it needed the support of the military, should we not conclude that the two must go hand in hand?<span> </span>Not so. Space exploration could have taken a different route, with success.<span> </span>For one thing because there may be good reasons to engage in it -- as we have seen in previous chapters.<span> </span>And for another, because space enthusiasts may have come up with great propaganda all the same.<span> </span>National prestige alone, even in the absence of a cold war, can be enough of a motivation in some circumstances.<span> </span>As DeGaulle said in ushering France into the space age, "We must invest constantly, push relentlessly our technology and scientific research to avoid sinking into a bitter mediocrity and being colonized by the invention and capacity of other nations."<span> </span></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Still it is obvious that without science and technology we would not have the capacity to destroy our planet.<span> </span>That I must grant.<span> </span>In response, however, I would like to tell a story with a relevant moral.<span> </span>Imagine that a group of humans is marooned in a remote island.<span> </span>One among them, an extremely clever scientist, figures out that a massive earthquake is going to destroy the island in one year. Scientific knowledge would prompt these people to undertake a dangerous journey that they might not survive, leading them to die sooner than if they had stayed in the island (to be successful, the trip must begin almost immediately).<span> </span>On the other hand ignorance would be bliss.<span> </span>But only for a year. <span> </span>What I want to argue is that even though science may increase our chances of disaster in the near future, it may also save us from perhaps greater disasters and allow us to postpone extinction.<span> </span>And in this task space exploration has a significant role to play.<span> </span>The goal of space exploration, Oberth wrote, is "To make available for life every place where life is possible.<span> </span>To make inhabitable all worlds as yet uninhabited, and all life purposeful."</span></p> <p class="MsoNormal"> </p> </div></div>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-15641840168481829512011-10-24T22:03:00.000-07:002011-10-24T22:05:03.409-07:00The Star Wars Defense<div id=":5w" class="ii gt"><div id=":5x"> <p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">Chapter 9C</span></b></p> <p class="MsoNormal"><b><span style="font-size:12.0pt;color:black"> </span></b></p> <p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">The Star Wars Defense </span></b></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black">Another contribution of space to our actual situation is often mentioned.<span> </span>Satellites are integral part in military communications and reconnaissance. But on the whole this has been more of a benefit than not.<span> </span>It was precisely the existence of such satellites that made it possible for the Kennedy administration in the U.S. to sign a test ban treaty with the Soviets.<span> </span>The days of such testing seem a remote memory today, but we must not forget that extremely powerful devices were routinely exploded in the atmosphere, with potentially disastrous effects.<span> </span>And even though a ban was in the interest of both parties, it was difficult to get around the suspicion that the other side would cheat.<span> </span>Together with seismographic methods and other techniques, reconnaissance satellites gave the needed assurances.<span> </span>Little can be done to hide an explosion of several megatons from a good camera overhead.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Satellites also guide “smart bombs” and give the military information needed to invade other lands.<span> </span>But then again, cooperation with the military need not be evil.<span> </span>It all depends on the enemy and the war.<span> </span>Besides, the main motivation for the development of “smart bombs” is to maximize the destruction of military targets while minimizing civilian casualties.<span> </span>This is hardly the basis for an indictment.<span> </span>Now, a new direct application of space technology to war may be the conversion of an airplane designed to fly in the thin Martian atmosphere into a spy plane (for it could fly high enough to avoid standard ground-to-air missiles).<span> </span>As we have seen, though, the spying made possible by space technology has been on the whole beneficial.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Let me leave behind for the moment this examination of past and present and concentrate for a while on the future. There are two main ways in which space can be seen as worsening our situation.<span> </span>One is that weapons more formidable may still result from space technology.<span> </span>The other is that by developing that technology we make the world more unstable.<span> </span>What those formidable weapons might be is largely unknown.<span> </span>A suggestion one hears from time to time is that big rocks could be aimed at the Earth from the Moon.<span> </span>They would be accelerated to escape velocity by electromagnetic forces, and their course toward their Earth target would be corrected by pretty standard guidance techniques. The energy released by the impact of a large rock could cause extraordinary damage.<span> </span>To mount such an attack, a country would require a rather substantial base on the Moon.<span> </span>This base could be underground, and presumably easy to defend. I think that Gerard O'Neill's efforts to design a mass driver to put lunar materials in orbit -- basically the technology for the Moon slingshot -- shows that the military applications are not so readily at hand.<span> </span>The rocks would have to be very big to be effective as weapons and follow a very precise trajectory to fall on the right target.<span> </span>Nonetheless, I suppose that sooner or later such a weapon may be feasible.<span> </span>But I am not sure how the situation would be radically altered.<span> </span>What kept ICBM's in their silos had nothing to do with how easy the silos were to defend.<span> </span>It had all to do with the fear of retaliation upon the society that launched them.<span> </span>Similar remarks should apply to the proposal to build a gigantic solar collector in the Moon to energize a very powerful beam, a death ray, that would vaporize any nation incautious enough to become our enemy.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Another possible nightmare connected with space exploration may come at the time when we make serious attempts to travel to the stars.<span> </span>A hydrogen bomb releases only a small fraction of the energy "frozen" in matter.<span> </span>To achieve the relativistic speeds necessary in star travel we must find practical ways of releasing far larger fractions of energy.<span> </span>The problem is that, with such a technology, it might be possible to make bombs monstrous enough to blow our planet to bits.<span> </span>In that case, however, retaliation would be rendered at once impossible and redundant.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Some evidence suggests that a full-scale attack by one superpower upon the other might be enough already to destroy the human race even if there is no response.<span> </span>According to Carl Sagan and other researchers, a global nuclear war would radically affect the atmosphere, both by the amount of radioactive dust that would circle the planet and by the making it poisonous to terrestrial life.<span> </span>Although this possibility requires a rather pessimistic reading of "Nuclear Winter" scenarios, it should give further pause to nuclear adversaries.<span> </span>As our destructive power increases, to kill may well be tantamount to suicide. This may well show that to build more weapons is sheer folly.<span> </span>We should realize, however, that there is a clear sense in which more offensive power cannot make matters worse.<span> </span>When you have a bazooka pointed at someone's head, bringing a far bigger bazooka does not really alter the situation all that much.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>The other way in which space may presumably worsen the situation is by making it more unstable.<span> </span>One possibility much discussed in the recent past was the defense system proposed by President Reagan of the U.S.<span> </span>This system, popularly known as "the star wars defense," would have employed gigantic lasers or particle-beam weapons to knock out ICBMs in flight.<span> </span>Normally the atmosphere would dissipate the impact of such weapons, but since ICBMs must fly in thin regions, they might be easy prey.<span> </span>There were several formidable problems with such a scheme.<span> </span>The first was that the technology required went far beyond the state of the art.<span> </span>The second was that several easy countermeasures were open to the other side.<span> </span>And the third, and most decisive, was that according to the most optimistic reliable estimates such a defense would probably be no more than 75% effective.<span> </span>Since at the earliest time when the system could have been installed, each side could have owned at least 10,000 warheads, the successful 25% would be more than enough to put an end to things human.<span> </span>Even 99% effectiveness would allow for incredible devastation.<span> </span>Although such high level of effectiveness was never in the cards, imagine that a vigorous program of research could have improved the power of lasers and the means of detection of ICBMs to the point that a 100% effective defense had been possible in a few decades.<span> </span>Since the proposal by the American president included making the technology available to the other side, ICBMs would have become obsolete.<span> </span>In this way space would have done away with its main contribution to the anxiety of the Cold War.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>In reality, President Reagan's scheme was as pointless as it was expensive: A star wars defense cannot end the threat of annihilation.<span> </span>For the laser beams and the particles shot from low orbit could not penetrate the atmosphere to knock out also bombers and cruise missiles, or even missiles fired from submarines close to the target.<span> </span>That is, even with all the ICBMs neutralized, the Soviet Union and the United States had ample nuclear alternatives to destroy each other and human civilization.<span> </span>In the case of a real war, our celebration of the complete success of Star Wars against ICBM's would have lasted only the few hours that it would take for cruise a missile to barely clear the last hill on its journey to us . . </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Whereas some hope that space technology can help us slay the dragon whose fire other technology ignited, others worry about the increasing reliance on satellites for military operations, especially now that it is possible to attack and destroy those satellites.<span> </span>This is seen as one more instance in which space technology brings us to the edge of disaster.<span> </span>But we should notice that a country whose military communication satellites were destroyed would feel inclined to attack mainly because it would reasonably interpret the destruction of its satellites as the prologue to total war.<span> </span>A country could get away with the destruction of another's satellites only if the other could not find out about it.<span> </span>Since this is not so, it seems unreasonable to suppose that space technology has made matters worse.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>It is true that in space we can find more reasons for fighting than we already have.<span> </span>If we discover a great treasure in the Moon we may resent any attempts to take it away from us.<span> </span>And our satellites have become such valuable commodities that we would not like to be deprived of them.<span> </span>But we cannot blame space technology in this regard any more than a tribe can blame their canoes for enabling them to discover good hunting grounds downstream, grounds that may become a source of quarrel with another tribe.</span></p> <p class="MsoNormal"> </p> </div></div><img class="mL" src="https://mail.google.com/mail/images/cleardot.gif" alt="" />Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-37236888195945716632011-10-15T23:44:00.000-07:002011-10-15T23:46:54.771-07:00V-2 Rockets and Bombs<div id=":5w" class="ii gt"><div id=":5x"> <p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">Chapter 9B</span></b></p> <p class="MsoNormal"><b><span style="font-size:12.0pt;color:black"> </span></b></p> <p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">V-2 Rockets and Bombs</span></b></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black">Even though rockets had been used for military purposes since the 1200s, they had never been particularly effective as weapons. But in the 1930s the needs of the German military began to converge with those of the VFR.<span> </span>The main problem for the rocket enthusiasts was the lack of financial support for their activities.<span> </span>They resorted to all sorts of stratagems to raise money.<span> </span>One member by the name of Valier sold Opel on the idea of trying rockets to propel automobiles.<span> </span>This scheme brought in some funding until Valier was killed testing one of his contraptions.<span> </span>The VFR leader, Rudolf Nebel, talked the city of Magdeburg into supporting rocket research that would lead to an experiment sure to make the city famous.<span> </span>At the time there were in Germany many crank theories supporting the view that the Earth was a hollow sphere and we lived in the inside, with our heads, not our feet, pointing to the center.<span> </span>A rocket with a human observer in it could go up a few miles and decide once and for all what the real shape of the Earth was.<span> </span>Nothing but extended survival for the VFR came of the project.<span> </span></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Into this opportunistic search for funds walked the German army.<span> </span>The treaty of Versailles, after WWI, forbid the German development of long-range, heavy artillery.<span> </span>But there was no mention of rockets anywhere in the treaty.<span> </span>A young member of the VFR, Wernher von Braun was able to interest the army generals in his projects, a task facilitated by the fact that he was an aristocrat and the son of the minister of agriculture.<span> </span>Initially the army support was small, but as the tensions in Europe grew and the task of rearmament went into full swing, young von Braun very adeptly played the German armed services against each other (both the army and the air force saw the rocket as their domain).<span> </span>All the while, the story has been told, von Braun and his cohorts kept on designing the future space ship.<span> </span>According to him, "An unbiased visitor to the planning group at Peenemunde would have heard little, if anything, discussed which related to other matters than reaching out into space . . . ."<span> </span>But when it came to economic support, all the talk was of the terrifying weapon they were developing for the fatherland.<span> </span>Their final product, the V-2 rocket, was indeed terrifying.<span> </span>Many a British nightmare began with the horrible whistle of the rocket as it cut through the London night on its mission of death and destruction.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Even if the VFR used the bombing of London to finance space flight ultimately, a critic may still deny them absolution.<span> </span>Moreover, he may argue that this episode is a clear instance of how the quest for space made for more misery than the world would otherwise have endured.<span> </span>And he may also point out how easy it is for scientists to sell their souls to the devil.<span> </span>Oberth thought that space would bring about a more harmonious future.<span> </span>So did the pioneers of aviation.<span> </span>Once in the air, human beings would realize the unimportance of the geographical and political barriers between them.<span> </span>In a similar vein, some believe now that as humans look back at the globe of the Earth from space, they will be struck by the revelation that we are all children of the Mother Earth and therefore brothers.<span> </span>There lie the beginnings of real peace.<span> </span>Ho Chi Minh, the leader of Vietnam during the war against the USA sent a message of congratulations to its enemy on the occasion of the first lunar landing by the Americans. Perhaps that revelation of brotherhood will become widespread.<span> </span>But only folly would lead us to expect that it can guarantee peace.<span> </span>Brothers are sometimes the worst of enemies.<span> </span>As for the aviators, not long after being awed by the prospects of peace, they were killing each other and reducing cities to rubble.<span> </span>And in spite of the spectacular adventure of the Apollo flights to the Moon, the war in Vietnam continued for several more years.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Nevertheless, let us not leave the V-2 incident unexamined, for that incident gives so much plausibility to the notion that space technology is bound to bring us to grief.<span> </span>We assume that anything that furthered Hitler's cause was evil, therefore the V-2 was evil.<span> </span>But did the V-2 further Hitler's cause?<span> </span>To believe Dornberger, the German general in charge of the V-2 project, it did. He recalls that Hitler apologized to him for not having grasped the significance of the weapon years earlier--the first time in his life that Hitler had apologized.<span> </span>But the man who kept the books, Albert Speer, the minister of munitions, thought that the V-2 had been a terrible waste of manpower and resources.<span> </span>As he put it: "49,000 tons of explosive were dropped on Berlin alone, by which 20.9% of the dwellings were seriously damaged or totally destroyed.<span> </span>In order to direct the same quantity against London, we would have had to employ 66,000 great rockets."<span> </span>Consider for a moment that Germany fired against England a grand total of 1340 V-2s!</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>By contrast, one American B-17, a long-range bomber, cost six times as much as one V-2 but carried three times as many explosives and could be used many times over.<span> </span>It has been suggested that Germany would have been better off building airplanes instead.<span> </span>This is doubtful.<span> </span>Radar gave the allies a great advantage in defending against the German air force, and thus more airplanes may not have made the difference.<span> </span>Fighters could, of course, be used to defend Germany against the attacking bombers; but it is not clear that the Germans had the gasoline for those extra airplanes while, as Dornberger claimed, the V-2s used alcohol extracted from potatoes.<span> </span>Dornberger, however, fails to take into account the diversion of coal from the production of gasoline (the Germans made synthetic gasoline) to factories producing not only the alcohol but also the more esoteric fuels used by the rockets. Nor does he take into account that cars and trucks could and did run on alcohol.<span> </span>Indeed at Peenemunde, the base for the V-2, the carburetors of trucks had been modified so they could run on rocket fuel.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Whatever the final disposition of the choice between V-2s and airplanes, there is a more straightforward comparison to determine the effectiveness of the V-2.<span> </span>The natural competitor of von Braun's rocket was the V-1, or buzz bomb, a pilotless plane forerunner of the cruise missile, and not a rocket designed with space in mind.<span> </span>According to calculations made by David Irving and later confirmed by Speer, the V-1 killed twice as many Britons for half the production cost of the V-2.<span> </span>Toward the end of the war the British were able to shoot down most V-1s, but the Germans could have instituted easy modifications that would have preserved the success of the V-1.<span> </span>They did not do so because von Braun had convinced them that his big liquid-fuel rocket was the way to go.<span> </span>As Bainbridge concludes, "By any criteria, the V-2 was not a cost-effective weapon. It could not match the performance of much simpler weapons systems, yet drained money, materials, and talent from its sponsors."<span> </span></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Sometimes it is suggested that the V-2 could have carried an atomic warhead.<span> </span>But the Germans did not have one.<span> </span>And if they had, the V-2 could not have delivered it (the payload of a V-2 was less than a ton; an early atomic bomb weighed four tons).<span> </span>Suggestions that the Germans could have combined several V-2s for that purpose, or that they could have built a rocket capable of hitting targets in the U.S. do not stand up to close scrutiny.<span> </span>The same can be said for the notion that a von Braun design had provided an effective antiaircraft missile.<span> </span>But I will let the interested reader consult Bainbridge's analysis (pp.92-122).<span> </span>For our present purposes the important result, at least in this case, is that space technology does not seem to have made matters worse for mankind. If anything the case goes in the opposite direction.<span> </span>This, of course, may not change our moral evaluation of von Braun and his group.<span> </span>Bad intentions or plain callousness are in themselves worthy of blame.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>After the war, the V-2 was used for scientific research at high altitude, a task for which it was very well suited.<span> </span>Its military used was limited, as was that of its direct descendants, the Russian T-1 and the American Redstone.<span> </span>And the reason was simply that a rocket was then too expensive and complicated a means of delivering conventional explosives.<span> </span>Nevertheless, opportunity would again come von Braun's way, now with his group forming part of the American rocket program, and for Korolyov, von Braun's Russian counterpart.<span> </span>At first it was the Army's interest in a rocket that might carry atomic warheads; and then in the 1950s, with the development of compact hydrogen bombs, the space rocket seemed to have become at last an effective instrument of war.<span> </span>Thanks to the descendants of the V-2 that terrorized London, man could now make short work of ending all life on Earth.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>It is clear that the cold war led both Americans and Russians to spare no effort in developing technology for war.<span> </span>And there is no question that the quest for space played a part in putting the human race under the threat of nuclear annihilation.<span> </span>But as in the case of the V-2, the matter is not all that simple.<span> </span>First of all, that threat would have been there independent of rockets.<span> </span>Bombers would have been sufficient all along.<span> </span>Second, for all the anxiety that threat caused, some argue that the fear of mutually assured destruction (MAD) actually prevented a third world war.<span> </span>And third, the contribution of space technology is ambiguous.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>The first point is fairly obvious.<span> </span>The main role of rockets was to make the time of flight so short -- from a few minutes to half an hour depending on their location -- that in case of a confrontation it would have been very difficult to correct any mistakes. To some critics this is a terrible indictment of space technology. And so is the mere fact that rockets have given us one more way of making the destruction of life possible.<span> </span>But this is all a matter of perspective.<span> </span>Let us consider the two indictments separately.<span> </span>It is true that shortening the time from the decision to attack to the actual explosion did not allow for much flexibility.<span> </span>Nevertheless, the problem of inflexibility still existed with bombers and cruise missiles that could not be called back -- as it was the case with the American weapons -- so without rockets the world would get a reprieve of a couple of hours.<span> </span>Once the decision to attack was made, the result would be the same anyway.<span> </span>In any event, from the point of view of the supporters of MAD, the variety and efficiency that rockets offered simply made us work so much harder to make sure that we did not launch an attack.<span> </span>And that was on the whole for the best.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>People who hold this view need only point out that the Soviet Union and the United States had such mutually repulsive political systems that a global war would have been inevitable without MAD.<span> </span>And even though the two superpowers constantly engaged in surrogate wars, and even though many other countries insisted in adding their own ghastly contributions, during the Cold War, the world endured nothing comparable to the devastation of WWII.<span> </span>Indeed, it is easy to imagine that a conventional war between the two superpowers, probably in the 1950s, would have dwarfed the confrontation with Hitler.<span> </span>Thanks to nuclear weapons, there was no world war because to start one was to commit suicide.<span> </span>The anxiety produced by MAD was difficult to bear.<span> </span>But given the alternative -- and I mean a conventional, not a nuclear, WWIII -- there were those who would rather be anxious.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>The notion is then that, with stakes so high, the world has had to be very careful.<span> </span>But what makes some critics despair is that an accident or a misunderstanding could have brought about the end of the world.<span> </span>As the means of setting the bomb off multiplied, the probability that it would increased.<span> </span>Besides, the shorter the fuse, the harder it is to evaluate whether reports that it has been lit are genuine.<span> </span>A country may retaliate, thinking itself under attack, in a case in which more time could have turned up a computer malfunction or a strange echo on a radar screen rather than an incoming ballistic missile.<span> </span>But on the other hand, the more its means of retaliation, the less a country will fear that it will not be able to get even. In such a case, a country may be more willing to take the chance that its opponent has not really launched a first strike--and more willing also to recognize an accident for what it is.<span> </span>The fewer its means of retaliation, the more paranoid a country may be, and thus the more likely to attack.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>In this matter, as in most political matters, people hold strong opinions without hesitation.<span> </span>But it is seldom easy to see why the argument can cut only one way.<span> </span>Nevertheless, let us grant -- for the sake of discussion, if nothing else -- that MAD was a terrible thing, and that the world would have been better without it. Is the link between space technology and the nuclear threat therefore as firm as many believe? </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>That matter is not so clear either.<span> </span>During a short time in the 1950's, space rockets became suitable vehicles for the newly invented hydrogen bombs.<span> </span>But once the Russian and American space programs began in earnest, the size and power of the new rockets were generally far in excess of what the military needed.<span> </span>Even at the time when the first ICBMs were being built, the goal could have been accomplished without liquid fuel rockets, that is, without space rockets.<span> </span>Solid fuel rockets, it turns out, can serve the military purpose with greater reliability and safety.<span> </span>In fact, in several instances the space rockets were out of the question.<span> </span>The Navy, for example, had no use for a liquid fuel rocket that could be fired only in near perfect weather.<span> </span>The Navy feared that any rocking of the ship could make the rocket explode prematurely -- on deck.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Of course, a solid fuel rocket does not offer as much control.<span> </span>But then the task did not involve putting anything in orbit, and, in any event, given the devastating power of a hydrogen bomb, extraordinary precision was not at a premium. <span> </span>Much later when increased precision was required, new guidance systems had become available for the solid fuel rockets.<span> </span>Thus the military could have had its ICBMs without space; and to concur with Bainbridge, perfect hindsight makes us see that the military should have gone strictly with solid fuel rockets.<span> </span>The direction the military actually took favored space flight and not the means of destruction.<span> </span>And it took that direction because space enthusiasts like von Braun could always make great propaganda out of the technological success of the V-2 and the myth that surrounded it.<span> </span>Without that myth, military rockets would have been very different.<span> </span>As Bainbridge puts it: “The military advantages of solid fuels include cost, storability, reliability, and simplicity.<span> </span>These advantages must be foregone by space vehicles to achieve greater power and control.<span> </span>By its striking superiority over contemporary solid-fuel rockets, the V-2 pointed the direct way toward space but led military technology on a detour."</span></p> <p class="MsoNormal"> </p> </div></div>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-70307669327006319472011-10-08T22:59:00.000-07:002011-10-08T23:03:02.182-07:00SPACE TECHNOLOGY AND WAR<div id=":84" class="ii gt"><div id=":85"> <p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">CHAPTER 9A</span></b></p> <p class="MsoNormal"><b><span style="font-size:12.0pt;color:black"> </span></b></p> <p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">SPACE TECHNOLOGY AND WAR</span></b></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"> </span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black">One of Rousseau's complaints against the arts and the sciences was that they weaken the military might of a society.<span> </span>"All examples teach us," he said, "that in military affairs...study of the sciences is much more apt to soften and enervate courage than to strengthen and animate it." Perhaps it was still possible in the 18th Century, when he wrote, to believe that the sciences were luxuries of no practical military consequences -- although even then the new science had brought great advances in ballistics and other military fields.<span> </span>Today those who share Rousseau's suspicion of science do so for different reasons.<span> </span>He worried that science made us if anything less formidable.<span> </span>They worry that it makes us far too formidable.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>The proponents of space exploration generally have a benign view of what the enterprise has to offer, although it is not uncommon to see space activities funded precisely because some military advantage is likely to result from them. The serious objection is not, however, that there is a connection between space technology and the military, for after all there have been times when helping the military was the right thing to do (fighting against Hitler, for example).<span> </span>The objection is rather that space technology puts into the hands of man tools that he cannot fail to mishandle.<span> </span>There is an evil side to man, and so whatever discoveries science makes will eventually visit pain and misery upon the human race. Space science and its accompanying technology are no exception. If anything they confirm the suspicions against science in general.<span> </span>Is it not true that rockets have been used to kill and terrorize in the past?<span> </span>Is it not true that for decades they were the very means by which the entire planet could have been brought to nuclear annihilation at a moment's notice?<span> </span>Are they not still a great threat today?</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>The point is not merely that there is a connection between space and grief.<span> </span>The point is rather that the connection is somehow unavoidable, that you cannot have one without the other.<span> </span>Thus, the more space technology progresses, the more acute the grief. This far more sweeping claim requires that we look into the history of space exploration and its likely future for clues of such inherent connections with destruction and evil. Indeed we must keep in mind that this claim often gains plausibility in the first place because of appeals to history -- mainly to the role of the German V-2 rockets in WWII and of the intercontinental ballistic missiles during the Cold War.<span> </span></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>The need to examine this objection in a historical context cannot be stressed too much. Some may argue that the relevant issue is whether space technology will make war inevitable in the future, whatever its role might have been in the past.<span> </span>But this line of argument operates in a rhetorical vacuum.<span> </span>An estimate of the contribution of space technology to war should presumably be supported by reasons, by an account of the causal and probable connections involved.<span> </span>And how are those reasons going to be assessed?<span> </span>On their merits, one might hope.<span> </span>But what are their merits?<span> </span>What makes causal and probable connections plausible in the first place?<span> </span>I submit that these difficult matters are most often influenced by the way we have learned to judge.<span> </span>And what has determined that learning if not our perception of how similar matters have been resolved?<span> </span>We appeal, that is, to our experience, and in the last analysis, to history.<span> </span>At the very least a brief look at history is necessary, then, to unearth assumptions which otherwise may be innocently smuggled into appraisals of the future.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>The wish to explore beyond the confines of our own world is very old. By 180 AD it received full treatment in Lukian's <i>Vera Historia</i> (True History), in which travelers go to the Moon when a giant whirlwind picks up their ship from the ocean. In 1634 the famous Johannes Kepler wrote <i>Sleep</i>, a novel about a trip to the Moon.<span> </span>With the advent of the industrial revolution, several would-be inventors tried their imagination at mechanical contraptions that could turn such trips into more than dreams, although their colorful ideas had little to do with the actual development of rocketry many decades later.<span> </span>In Russia there was Kibal'chich, who spent his time designing explosive devices and rocket aircraft, while ignoring his trial for blowing the Czar to bits in 1881.<span> </span>In Germany there was Ganswindt, who worked on a hopeless steam jet to propel his spacecraft.<span> </span>And everywhere there were fiction writers taking their readers on trips that engineering could not yet make available.</span></p> <p><span style="font-family:"Times New Roman","serif""><span> </span>The theme of space travel was in the air, and around the turn of the century the real pioneering work was finally carried out. By then science and technology had caught up with the old dreams to the point that not one but three independent investigators provided the foundation of space rocketry. The Russian Tsiolkovsky was the earliest, then came Goddard in the U.S., and finally the most influential of them all, Oberth in Germany.<span> </span>The first thing these three men had to do was show that space flight was indeed possible. Their solution to this problem, as we will see, has some bearing on the issue of whether inherent connections exist between space technology and devastating war.<span> </span>And the problem was that, to many “experts” at the time, space flight seemed not merely far fetched but physically impossible.<span> </span>Some disheartening calculations, for example, showed that however efficient the production of thrust, no rocket could raise its own mass into orbit.<span> </span>But as the pioneers showed, even the most sophisticated impossibility proofs could be gotten around by the very simple but ingenious idea of using multi-stage rockets.<span> </span>The first stage gives the whole rocket an initial boost and then separates.<span> </span>At that point a second stage takes over the task of pushing a lighter vehicle with a now shorter distance to climb.<span> </span>One or two more pushes like that and the rocket achieves orbital velocity.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>A second barrier was overcome by the switch from solid to liquid fuels.<span> </span>Standard rockets generally used solid fuels, mostly gun powder, which lacked both the power and the control required for space flight.<span> </span>Tsiolkovsky and the other pioneers soon realized, however, that several mixtures of liquid propellants, particularly hydrogen burned with oxygen, could give rockets the desired performance.<span> </span>This is of particular importance to our question, as we shall see.<span> </span>Now, a quick comparison of liquid and solid fuels shows how right Tsiolkovsky was -- a most remarkable feat for a self-taught man who never gained entrance to the scientific or engineering circles of his day. Liquid propellants liberate more energy per pound than their solid competitors. (The following figures were given by John Shasta of the American Rocket Society in 1936, and appear in William S. Bainbridge's book <i>The Spaceflight Revolution</i>, from which most of the following account is taken).<span> </span>The best powder achieved 1870 BTU's; a mixture of methyl alcohol with oxygen, 3030; while hydrogen and oxygen combined gave 5760. Even in contemporary times the differences are pronounced: The solid fuel in the typical military rocket of the 1970's produced in principle an exhaust velocity of 2250 meters per second (m/s), a figure inferior to the 2750 m/s that Goddard had actually achieved with his small rockets decades earlier, and much below the 4200 m/s obtained by burning hydrogen with oxygen.<span> </span>At least until recently, the best that could be hoped for in future solid fuels did not measure up to the performance of liquid fuels in this respect.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>In the second important respect, control, the differences are just as pronounced.<span> </span>The difficulty with a solid propellant is that it tends to burn until it is exhausted.<span> </span>You cannot just shut it off and start it again.<span> </span>In a liquid system, on the other hand, you may always control the amounts of fluids intervening in a reaction -- you may increase it, decrease it, or turn it off altogether.<span> </span>And you can open the valves again and thereby restart the combustion that gives you the thrust. This fine control permits the appropriate accelerations at the appropriate times to maneuver the rocket into the desired orbit.<span> </span>And although the techniques to achieve this control were not easily acquired by rocket developers in the decades that followed, there was now a clear direction of research, as well as good reasons to think that the problems could be solved.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>The three pioneers also provided basic formulas for engine performance and specified likely vehicle trajectories.<span> </span>Now the goals were clarified, and so were the means for attaining them.<span> </span>Nevertheless, the move toward space did not quicken its pace for a long time.<span> </span>The few who were technically competent and who took the trouble to read carefully the works of the rocket pioneers may have realized the potential involved.<span> </span>But most technically qualified people regarded the topic with suspicion and did not bother themselves with an investigation of it.<span> </span>There is nothing conspiratorial or shortsighted in that attitude.<span> </span>Any scientist may well be bombarded with a myriad of ideas that he himself has not examined in detail.<span> </span>Which ones should he explore?<span> </span>Not all of them.<span> </span>He cannot.<span> </span>And surely not those that strike him as implausible or without foundation.<span> </span>Time is too short for that.<span> </span>Science changes because not all scientists are cut of the same cloth, and thus what seems preposterous to the majority may instead strike a resonant chord in a few others.<span> </span>Most beginnings are therefore small, and the development of space technology was no exception.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>The dreams of the pioneers were left for others to realize.<span> </span>Tsiolkovsky remained undiscovered and ignored.<span> </span>Goddard was very secretive about his own work.<span> </span>As Bainbridge points out, "He did not publish an account of his first 1923 engine firing until 1936, when the V-2 was already taking shape on German drawing boards.<span> </span>Complete reports of his experiments in the 1930s were not published until 1961, the year that Yuri Gagarin orbited the Earth."<span> </span>This situation was apparently more the result of his peculiar temperament than anything else.<span> </span>According to Bainbridge, "Goddard tended to ignore the work of other men in the field, was remiss in his correspondence with colleagues, refused to share his results, and would not participate in joint projects.<span> </span>He seemed to want to achieve successes...then burst upon the world in triumph."<span> </span>But one man alone could not achieve what took the efforts of many thousands.<span> </span>Such were the first quirky steps in the strange journey that took us to the Moon.</span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>As interesting as the lives and motivations of these men were, an account that would do them justice is beyond the scope of this book.<span> </span>For our purposes, it is enough to say that those motivations had more to do with the liberation of the human spirit, with its excellence, than with the destruction of other human beings.<span> </span>In Oberth's words: "...probably Mankind will even build spaceships sometime, make other planets habitable, or even establish habitable stations in space, and having become morally mature in the meantime, will bear life and harmony out into the cosmos."<span> </span></span></p> <p class="MsoNormal"><span style="font-size:12.0pt;color:black"><span> </span>Oberth presented his masterwork <i>The Rocket into Interplanetary Space</i> as his doctoral dissertation in 1922 (Goddard's crucial theoretical work preceded his by ten years, and Tsiolkovsky's by twenty).<span> </span>He was turned down with the advice to look for a more suitable topic.<span> </span>He refused, and then proclaimed that he could become a greater scientist than his examiners, "even without the title of doctor."<span> </span>His arrogance was not entirely misplaced.<span> </span>Within a year he had published his book, of which Arthur C. Clarke has said that it "may one day be classed among the few that have changed the history of mankind."<span> </span>In any event, it became not only a source of inspiration but also the textbook for the German rocket experimenters.<span> </span>One such group, founded in 1927, the VFR--Verein fur Raumschiffahrt (Society for Space Travel) -- was to prove of crucial importance.</span></p> <p class="MsoNormal"> </p> </div></div>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-74568335199556061652011-10-01T00:33:00.000-07:002011-10-01T00:34:52.085-07:00CAN SETI BE JUSTIFIED?<p class="MsoNormal" style="margin-top:0in;margin-right:.5in;margin-bottom:0in;margin-bottom:.0001pt"><span style="color:black">CHAPTER 8F</span></p> <p class="MsoNormal" style="margin-top:0in;margin-right:.5in;margin-bottom:0in;margin-bottom:.0001pt"><span style="color:black"> </span></p> <p class="MsoNormal" style="margin-top:0in;margin-right:.5in;margin-bottom:0in;margin-bottom:.0001pt"><span style="color:black"> </span></p> <p class="MsoNormal" style="margin-top:0in;margin-right:.5in;margin-bottom:0in;margin-bottom:.0001pt"><span style="color:black">CAN SETI BE JUSTIFIED?</span></p> <p class="MsoNormal" style="margin-top:0in;margin-right:.5in;margin-bottom:0in;margin-bottom:.0001pt"><span style="color:black"> </span></p> <p class="MsoNormal" style="margin-top:0in;margin-right:.5in;margin-bottom:0in;margin-bottom:.0001pt"><span style="color:black">Is SETI a waste of time and money? I do not think so.<span> </span>SETI does at least two valuable things. First, it provides an extraordinary opportunity for a shortcut in our search for life in the universe. For obviously, if we detect intelligent civilizations we will have settled the issue of the possibility of extraterrestrial life, which otherwise may take hundreds, perhaps thousands, of years to resolve, if it can be resolved at all by space travel. </span></p> <p class="MsoNormal" style="margin-top:0in;margin-right:.5in;margin-bottom:0in;margin-bottom:.0001pt"><span style="color:black"><span> </span>SETI’s chances of success may be slim, but if we do succeed the results would be of the greatest significance.<span> </span>SETI is like a lottery ticket: As long as the investment is small, we have little to lose and much to gain.<span> </span>That is pretty much the way the matter is being treated at the present time -- a budget in the few million over the next decade is a mere pittance as far as those things go. </span></p> <p class="MsoNormal" style="margin-top:0in;margin-right:.5in;margin-bottom:0in;margin-bottom:.0001pt"><span style="color:black"><span> </span>Second, SETI provides special motivation and in some cases inspiration for many researchers who work in areas related, however indirectly, to the issue of the origin and the evolution of life. Indeed, to be fair to the SETI enthusiasts, much of their work has concentrated on improving our knowledge of several of the links in the chain between the origin of the galaxy and the origin of life. The misleading use of probabilities comes more in the public relations effort than in the actual science. </span></p> <p class="MsoNormal" style="margin-top:0in;margin-right:.5in;margin-bottom:0in;margin-bottom:.0001pt"><span style="color:black"><span> </span>Another benefit of SETI is that as part of the task of identifying suitable stars it is necessary to improve our star catalogue for distances at least up to a few hundred light years away, which is the maximum radius of the volume that SETI will comb for intelligence in the near future.<span> </span>As new technology--radiotelescopes in orbit, for example-- increases the radius of the search, the map of our section of the galaxy is also bound to improve.<span> </span>This painstaking but necessary job of astronomical taxonomy has been neglected somewhat because it does not compare in glamour with the investigation of the many exciting phenomena that have come to light in the past three decades. SETI gives it the right spice to make it enticing enough.</span></p> <p class="MsoNormal" style="margin-top:0in;margin-right:.5in;margin-bottom:0in;margin-bottom:.0001pt"><span style="color:black"><span> </span>Whether SETI succeeds or not, however, I suspect that its main possible contribution lies elsewhere.<span> </span>Just as exobiology can provide a very useful context in which to ask questions about the origin and evolution of life, SETI may become a useful framework to examine the nature of our intelligence and our technological civilization.<span> </span>And here I do not mean merely the determination of whether we should feel unique or ordinary as a species -- important as this matter may be -- but rather the ability to bring together many disciplines to investigate the origins and evolution of scientific culture.</span></p> <p class="MsoNormal" style="margin-top:0in;margin-right:.5in;margin-bottom:0in;margin-bottom:.0001pt"><span style="color:black"> </span></p> <p class="MsoNormal" style="margin-top:0in;margin-right:.5in;margin-bottom:0in;margin-bottom:.0001pt"><span style="color:black"> </span></p>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-52435304813909388192011-09-23T00:46:00.000-07:002011-09-23T00:48:40.713-07:00CHAPTER 8D ARE ADVANCED CIVILIZATIONS LIKELY? What events or processes would make it possible for our technological civilization to be the onl<div id=":9p" class="ii gt"><div id=":9q"> <p>CHAPTER 8D</p> <p> </p> <p>ARE ADVANCED CIVILIZATIONS LIKELY?</p> <p> </p> <p>What events or processes would make it possible for our technological civilization to be the only one in the galaxy?<span> </span>First of all, it may turn out that there are very few favorable planets. Our rather speculative theories on the formation of planetary systems could be wrong, for example, although today the evidence tends to be favorable. <span> </span>The fact that Mars and Venus are so different from the Earth indicates that there may be only a small band in a solar system where a terrestrial planet could give rise to life. Thus, even if planets of terrestrial size form, they may be just outside of that "green band," as Mars and Venus might be.<span> </span>Still that may leave many terrestrial planets at the appropriate distance from their stars.<span> </span>Some new computer models, however, predict that rocky planets like Earth are likely to be thrown out of their solar systems, or that few of them would have moons large enough to stabilize their rotations, and thus provide a climate favorable for life.<span> </span>But surveys of actual exo-terrestrial planets found suggest that there should be many rocky planets in the galaxy.<span> </span>But let me make allowances here and concentrate instead on some crucial assumptions at the heart of the issue.</p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;">EXTRATERRESTRIAL AND HUMAN SCIENCE<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1329539a9803aefb__edn1" name="1329539a9803aefb__ednref1" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[1]</span></span></span></span></a></span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;">Travel teaches us not only about other places and people but also about ourselves.<span> </span>Likewise trying to understand what other intelligent life might be like teaches us about our own intelligence.<span> </span>And trying to understand how alien intelligence may view nature teaches us about what our own views of nature amount to.<span> </span>In SETI we find almost bare many common assumptions about the origin, development, and nature of science.<span> </span>Thus from an analysis of SETI we may be able to draw some interesting philosophical lessons.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1329539a9803aefb__edn2" name="1329539a9803aefb__ednref2" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[2]</span></span></span></span></a></span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>In this section I will be concerned mainly with three notions that are frequently advanced by SETI proponents.<span> </span>The first notion is that once life appears on a planet, intelligent life is also very likely.<span> </span>The second is that once intelligence appears on a planet, science itself is likely.<span> </span>The third is that all scientific civilizations have something in common (i.e., an overlap in their scientific views of the world) and thus the basis for the beginning of communication between them<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1329539a9803aefb__edn3" name="1329539a9803aefb__ednref3" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[3]</span></span></span></span></a>.<span> </span>The first two notions are advanced to support the contention that there is probably someone to look for.<span> </span>The third gives us hope that contact, if we make any, will be productive.<span> </span></span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>In spite of their initial plausibility, I will argue that these notions are plagued with less than obvious assumptions at many levels, and that they lead to a questionable account of our views of nature.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>SETI proponents believe that life can begin elsewhere, that once it begins it is likely to become more complex, and that complexity produces intelligence.<span> </span>Presumably, as time goes on, intelligence will improve its attempts to understand what the world is like -- thus begins the almost inevitable road to a technological civilization.<span> </span>Whether life can begin elsewhere is a matter of great controversy, as we have seen.<span> </span>But I will grant for the sake of argument that it could.<span> </span>In the same spirit I will grant that, at least for some time, the complexity of life may increase; and I will also grant that intelligence is the result of certain complex biological organizations.<span> </span>But granting all these crucial assumptions of SETI is not the same as granting that alien technological civilizations are very likely.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Let me take stock of what I have granted.<span> </span>After some primitive form of life appears on a planet, it will not remain uniform for long.<span> </span>Small variations in the environment and other factors will bring about diversity.<span> </span>Of course, diversity is not the same as complexity, but it gets us on the road to it.<span> </span>For diversity means that there will be different kinds of biological structures and different ways of interacting with the environment.<span> </span>And the possibility then arises that eventually some of these structures and functions will combine.<span> </span>A and B may come to work together and a new structure C will arise to coordinate their work.<span> </span>And now A, B, and C together will form a new whole that is more complex than either A or B as separate individuals.<span> </span>During the first couple of billion years of life on Earth, prokaryote cells were the most prevalent, perhaps the only form of life.<span> </span>These cells in which the chromosomes are not protected inside a membrane (the nucleus) eventually led to cells with nuclei (eukaryotes), which are more complex.<span> </span>According to Lynn Margulis, this important step came about by the symbiosis of different kinds of prokaryote cells.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1329539a9803aefb__edn4" name="1329539a9803aefb__ednref4" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[4]</span></span></span></span></a> In any event, once cells with nuclei appeared it was possible to form organisms that combine many of these cells, sometimes billions of them.<span> </span>These organisms are very complex wholes of eukaryote cells that perform many different but coordinated functions.<span> </span>Although after billions of years the increase in the complexity of life can be considerable, complexity is not always bound to increase with time.<span> </span>Changes in the environment of a planet, some of them caused by life itself, may make it very difficult for all but simple organisms to survive on that planet.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Let me concentrate now on a particularly interesting kind of complexity.<span> </span>Eventually some Earth animals developed intricate patterns of muscles and bones so they could move about, external senses to give them information about the world, and internal senses to monitor a variety of organs.<span> </span>It does not take much to see the advantage of coordinating these functions.<span> </span>A successful predator not only sees the prey but also can move so as to catch it.<span> </span>On Earth, a popular answer to this problem of coordination is the central nervous system.<span> </span>And this is an interesting answer because it is in connection with a highly complex central nervous system that intelligence becomes conspicuous.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>A highly complex central nervous system is not limited to just one way of handling the information that it receives from the world: It can rout and combine information in a variety of ways; it can compare sense modalities; it can store information and consider alternative actions; that is, it can make use of memory and imagination.<span> </span></span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Visual perception is a good illustration of this kind of complexity.<span> </span>At a very primitive level we may suppose that the detection of light is enough for a certain organism, in order to move towards or avoid the light.<span> </span>The next step comes when the organism gains an advantage by being able to discriminate visually between objects, which may be achieved by making internal representations of those objects.<span> </span>These representations grow in sophistication, and the corresponding nervous structures in complexity, when the "input" from the eyes is coordinated with that from other senses.<span> </span>For example, when we are looking at a painting of a group of people our eyes are not stationary.<span> </span>First of all, the eye muscles make the eyes scan continuously.<span> </span>Second, our heads move sideways as well as up and down.<span> </span>Our whole bodies may also move, carrying our heads, and thus our eyes along.<span> </span>But the images of those people remain stationary.<span> </span>This is very different from, say, a video camera, whose images do move up and down or sideways, the more so the more unskilled we are at shooting with it.<span> </span>The reason our perceived images remain stationary is that the brain takes into account the automatic movements of the eyes as well as our body position in order to arrive at a perception that we can handle.<span> </span>The brain takes into account our body position by receiving information from the inner ear, which keeps track of the inclination of the body with respect to the Earth's gravitational lines of force, and from hundreds of skeletal muscles. </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Visual perception is also easily affected by the other senses.<span> </span>Take hearing.<span> </span>As we walk down a dark street at night we may perceive some bundles a few steps ahead.<span> </span>But at least one of those bundles suddenly becomes a sharp image when we hear the distinct growling of a guard dog.<span> </span>Perception also takes into account memory and imagination.<span> </span>An artist well trained in the history of art may see many more details in the painting and many more relationships between different elements of the painting than most of us can, just as a well trained naturalist can detect a rare bird in a bush where most of us can see only foliage.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>The more complex the central nervous system, the more complex the relationship between the organism and the environment, for the organism gains more degrees of freedom.<span> </span>Thus intelligence arises out of perception and other biological structures as the complexity of those structures increases.<span> </span>This account agrees with Piaget's description of intelligence as an instrument of adaptation not necessarily tied to the immediate and momentary demands of the environment (human beings, for example can figure out solutions to problems that will confront them far away and years hence).</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Let me sketch now the main hurdles that life has to overcome on its way to an advanced technological civilization.<span> </span>On this account, to say that intelligence is adaptive is to say that a highly complex central nervous system (or its equivalent) is adaptive.<span> </span>But then intelligence is adaptive only for certain kinds of organisms and not for others.<span> </span>It would be adaptive for primates, for example, but not for cockroaches.<span> </span>Let me illustrate the point by means of an analogy.<span> </span>It is well known that the opposable thumb is a highly adaptive feature of human beings.<span> </span>But it would not be so for horses.<span> </span>And it does not even make any sense to ask whether it would be for cockroaches, since roaches do not have the kinds of physical structures to which opposable thumbs can be attached. </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>We might think that roaches would be better off if they were smarter.<span> </span>But to put the point properly we have to consider whether roaches would be better off with more complex brains.<span> </span>And now we may begin to see the difficulty: There is a price to pay all along the way to intelligence.<span> </span>The price is that a complex brain demands a high metabolism.<span> </span>In a minor way the same point may be made about sight, which also seems to be quite an advantage.<span> </span>Imagine that a population of small mammals has come to live in dark caves.<span> </span>The brain structures of sight use a lot of energy, and so these mammals have to spend much time and work getting that energy.<span> </span>Since sight is of marginal advantage in the dark caves, the mammals that preserve sight are not as competitive as others that use only a fraction of the energy to enjoy improved hearing, touch and smell.<span> </span>It would be nice to have sight, but a mammal of that size can't afford the price to keep it.<span> </span>And for a population of sightless mammals it would make no sense to develop it.<span> </span></span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Likewise, an increase in the complexity of the brain requires that the organisms of the species in question gain some advantages that compensate for the price in metabolism that they have to pay.<span> </span>In the case of many species on Earth, including ours, those advantages have been there.<span> </span>But we should not expect that they would be there on any other planet where life may evolve.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Consider our kind of intelligence:<span> </span>mammalian intelligence.<span> </span>If the dinosaurs had not become extinct, mammals would have remained small vermin.<span> </span>Large mammals could not evolve because an increase in size would make it easier for dinosaurs to prey on them.<span> </span>But the price that mammals would have to pay for a bigger and more complex brain would probably be a bigger body.<span> </span>The point is that a species, or some other taxonomical category, can be successful enough on a planet to preclude the adaptation by other species that could some day evolve into creatures of high intelligence.<span> </span>In our own day, we ourselves are a cap on the development of intelligence by others.<span> </span>Suppose once again that raccoons become increasingly intelligent.<span> </span>As it was pointed out earlier, they would become such pests that humans would probably hunt them to extinction.<span> </span>Our very way of life tends to wipe out animals that enter into close competition with us.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Let us imagine a planet very similar to our own.<span> </span>Let us suppose that in that planet also the conquest of the land by fishes would have provided the necessary opportunities for an increase in the complexity of the brain.<span> </span>But let us also suppose that on that planet insects had already appeared on the land and were even more successful than on Earth.<span> </span>Because of their physical constitution, insects are not likely to grow large enough to develop the sort of large brain associated with intelligence.<span> </span>But insects have many adaptive features that serve them quite well.<span> </span>Thus they can be successful without being smart.<span> </span>In that planet they rule the land: Any fish that crawls out of the water will be eaten by insects, and if perchance eggs from that species are not only laid but hatched, the young fishes will be devoured.<span> </span>Intelligence as we know it is not likely to arise.<span> </span>The smartest being on that planet would be some kind of octopus.<span> </span>(It does no good to point to whales and dolphins--those are mammals and would have never evolved if vertebrates had not developed on land to begin with).</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Thus on other planets the cap may come from many different kinds of beings, even if their own intelligence is rather modest by our standards.<span> </span>All it takes is that in some other respects they can adapt <i>first</i> to the land, or whatever key environment we consider.<span> </span>But what enters into that timing?<span> </span>Most often just accidents of natural history.<span> </span>For example, it is possible that the disappearance of the dinosaurs may be traced in large measure to the collision of a gigantic asteroid with the Earth.<span> </span>But there is no guarantee, let alone a law of nature, that accidents of natural history are going to favor the development of high intelligence.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Let me imagine, nonetheless, that on some planets central nervous systems as complex as ours, or more complex, do evolve.<span> </span>Will technological civilization then come about?<span> </span>Not automatically.<span> </span>It has to be the right kind of intelligence:<span> </span>technological intelligence.<span> </span>The evolution of <i>human</i> intelligence is tied to the use of tools for hunting and many other purposes.<span> </span>But the evolution of this mode of interaction with the world makes sense only if you have the right kind of body.<span> </span>Dolphins, for example, which are creatures with complex brains and perhaps high intelligence (even if not in our class), have no hands, to say nothing of opposable thumbs.<span> </span>There is a clear sense in which we express our intelligence by having the appropriate bodily interaction with the environment.<span> </span>A technological intelligence would not be adaptive unless the right kind of body developed along with it.<span> </span>Spears may have been a sensible option for our ancestors, but harpoons would not have been so sensible an option for the ancestors of dolphins.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Nevertheless let me suppose that <i>technological intelligence</i> does arise and takes over a planet.<span> </span><i>Technological civilization</i> still does not follow automatically.<span> </span>A technological civilization is in part the result of complex social processes, thus the required type of intelligence must be not only technological but also social.<span> </span>But even if we have the evolution of this kind of intelligence, a <i>highly advanced</i> technological civilization may not arise.<span> </span>One reason is that high technology may well require the development of science.<span> </span>On our own planet a turning point came when the new science, culminating in Newton, was able to bring together astronomy and physics.<span> </span>But in a planet very similar to ours but perennially covered by clouds (or in a solar system traveling through a dust cloud) a comparable development of astronomy would be most unlikely.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Imagine, though, that we have a favorable physical environment where intelligent beings (both socially and technologically) can receive the inspiration and rewards that would take them on scientific paths blessed with the right kinds of intellectual breaks.<span> </span>We still cannot expect an advanced technological civilization.<span> </span>For having the right physical environment is not enough.<span> </span>Social factors may still prevent the development of science as we know it (let alone a more advanced science).<span> </span>It is plausible to suppose that the progress of science requires that ideas may be criticized and that alternative conceptions of the world be developed and defended even if a majority in a group do not agree with them.<span> </span>But in a species biologically inclined to a degree of social cohesion greater than ours, the criticism of the metaphysics of the society (e.g. of their account of the origin and nature of the world) may be seen, or felt, as a threat to the cohesion of the society and put down at once.<span> </span>It seems that in our world science barely made it; on that other planet science would have no chance.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>I do not wish to argue that a technological civilization could not arise on a different planet.<span> </span>My intent is merely to point out that the process is by no means automatic, that it requires many good breaks from natural history.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1329539a9803aefb__edn5" name="1329539a9803aefb__ednref5" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[5]</span></span></span></span></a><span> </span>A critic may argue that natural selection could have gotten around most if not all of the obstacles I have mentioned.<span> </span>All it takes is a bit of imagination, and we know how imaginative natural selection can be.<span> </span>For example, one of the reasons why advanced technology seems to need a social milieu to exist is that no one human being can fully develop a theory as comprehensive as, say, Newtonian mechanics<span> </span>(it took centuries), to say nothing of all the other branches of physics, chemistry, and so on.<span> </span>But even within one school it is difficult enough to come up with a few good ideas.<span> </span>To be able to see their flaws, possible means of improvement, or their connections to other areas of science often requires that we look at those ideas from many different points of view.<span> </span>One human being could not do all this.<span> </span>Science and advanced technology require a division of labor.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Imagine, however, a planet on which a single organism--not a single species, a single organism--comes to dominate even more than human beings do on Earth.<span> </span>This would be a strange organism that covers the environment like a comforter and grows larger by creating more branches of itself until it has finally covered much of the planet<span> </span>(if the food supply decreases this intelligent organism will either "farm" differently or drop off a few branches).<span> </span>Instead of a central brain, this organism has something that rather resembles a network of ganglia (large, complex ganglia to be sure).<span> </span>Although the action of the ganglia tends to be coordinated, in a network that large there must also exist a fair degree of decentralization.<span> </span>In that case ideas may be brought up by one particular ganglion and criticized by other ganglia, and so on.<span> </span>The concept of self of this organism may be quite different from ours, but the point is that in a single organism we may find the equivalent of a whole species.<span> </span>So this organism could develop an advanced technology even though, strictly speaking, it is not really social.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>It is clear, then, that if certain avenues of development are closed to life, natural selection may find others.<span> </span>But the price of alternative natural histories would be alternative forms of intelligence and eventually alternative ways of formulating views of the world.<span> </span>The reason is that the brains (or their equivalent) that would result from such radically different natural histories would arise from entirely different biological structures, and thus, in coordinating these structures, the developing brain would face different evolutionary problems and would have different solutions and opportunities at hand.<span> </span>In the neurological ward of a hospital we find people whose brain structures have been altered and who thus have peculiar ways of perceiving and conceiving of the world.<span> </span>Of course, their modes of thought are maladaptive, just as skeletal structures that deviate from the norm may be maladaptive in a human.<span> </span>But for different creatures, different brain structures and their corresponding modes of thought may be as adaptive as their different skeletal structures are.<span> </span>The consequence of this point is that the science of a species, or kind of organism, may be relative to its natural and social history.<span> </span>Thus species with very different natural histories may have little overlap in their scientific views of the world.<span> </span>If this is so, there would be much less in common to serve as the basis for interstellar communication with other technological civilizations than the proponents of SETI make it out to be.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Defenders of the SETI program often assume that advanced sciences and technologies must exhibit a high degree of convergence.<span> </span>The grounds for this assumption are presumably that, as science grows in scope, the brains that produce that science must reckon with all-pervasive features of the universe.<span> </span>Just as dolphins and fishes have very different evolutionary histories but similar shapes because they both live in water, so sciences that deal successfully with the basic forces of the universe must come to similar views.<span> </span>Nature presumably already offers many cases of convergence:<span> </span>placental and marsupial wolves, and camera eyes in squids and mammals, to mention only two of the most striking.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1329539a9803aefb__edn6" name="1329539a9803aefb__ednref6" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[6]</span></span></span></span></a><span> </span>Furthermore, when it comes to communication with advanced technological civilizations, we are talking about species that at a bare minimum have built means of electromagnetic transmission and may also have embarked in a program of space exploration.<span> </span>Their views may be superior to ours (having been around longer) but surely they must overlap with ours to some extent, for at least to some extent they and we are successfully applying the laws of electromagnetism.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Nevertheless the matter is not this straightforward.<span> </span>We must realize that even all-pervasive features of the universe would be interpreted differently by different scientific intelligences.<span> </span>As we have seen, a highly complex brain can deal with the environment in a very flexible and indirect manner.<span> </span>Moreover, it is not one brain but an ensemble of brains in very complex social relations that deal with the universe through science and technology.<span> </span>Whereas in the case of the ocean we had direct pressure (selection) on aquatic animals, in the case of the deep forces of nature we have many different ways of handling the pressure (indeed, a double tier of evolutionary slack).<span> </span>Even in the case of the ocean, animals with very different evolutionary histories have different shapes, as we can tell just by looking at crabs and salmon (fishes and dolphins are much more closely related).<span> </span>The very same "feature" of an environment impinges very differently on different organisms.<span> </span>A hot spring may kill some fish while making bacteria thrive.<span> </span>It is a mistake, therefore, to describe the situation as if different brains were dealing with the same problems.<span> </span>We rather have different brains dealing with different problems.<span> </span>Indeed those different brains will have (1) different starting points for inspiration, (2) different motivations, and (3) different social means of dealing with conceptual matters.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>As for the overlap in electromagnetic theory, we should guard against confusing an overlap in <i>performance</i> with an overlap in <i>content</i>.<span> </span>For in a limited domain two radically different views may allow us to do pretty much the same.<span> </span>As a guide to navigation, the astronomy of the ancients was not surpassed by the astronomy of Copernicus and Newton until long after Newton's death; and it remained competitive until the advent of recent technology.<span> </span>But according to the ancient view, the immobile Earth sat at the center of the universe while the stars were fixed on a gigantic sphere that rotated around the Earth.<span> </span>By keeping the stars in that sphere it was possible to calculate very precisely their position in the sky at any time of the year.<span> </span>And by reference to that position a sailor or an explorer could chart his course.<span> </span>In many respects it is still easier to apply the ancient view.<span> </span>In any event, to some extent the ancient and the modern views give us very similar practical guidance; they allow us, in a limited context, similar performances.<span> </span>But the views are not only different, they actually contradict each other: One forbids the motion of the Earth around the sun; the other requires it.<span> </span>If perchance we receive electromagnetic transmissions from another species, we should not conclude that those beings must have the equivalent of Maxwell's laws of electromagnetism.<span> </span>We may need Maxwell's laws in order to describe, to ourselves, what those beings do.<span> </span>But their actual "laws," if they even think in such terms, may not be any more equivalent to Maxwell's than the Greeks' lack of motion of the Earth is equivalent to Copernicus' motion of the Earth around the sun.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>We see then that there is no inevitable, nor highly probable, connection between the appearance of life and that of intelligence; nor between the appearance of intelligence and that of an advanced technological civilization.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>None of preceding rules out the possibility that extraterrestrial science exists. And even a small chance that it does may perhaps warrant a program to search for it, as we will see below.<span> </span>My aim up to this point has been to use the assumptions behind the optimism prevalent in SETI to investigate the conditions that make <i>human</i> science possible.<span> </span>We have seen that those conditions are many, and that to a large extent they depend on the vagaries of natural and social history. </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal"> </p> <div><br /> <hr align="left" size="1" width="33%"> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1329539a9803aefb__ednref1" name="1329539a9803aefb__edn1" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[1]</span></span></span></span></a> This section was excerpted and published as Chapter 2 of my <i>Evolution and the Naked Truth</i>, Ashgate, 1998.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1329539a9803aefb__ednref2" name="1329539a9803aefb__edn2" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[2]</span></span></span></span></a> An earlier version of this section appeared in <i>Explorations in Knowledge</i>, Vol. VI, No. 2, 1989.<span> </span>It was later reprinted as Chapter 2 of my <i>Evolution and the Naked Truth</i>, Ashgate, 1998, pp. 23-32.<span> </span>The conceptual underpinnings were first worked out in my <i>Radical Knowledge</i>, Hackett, 1981 (Avebury in the U.K.).<span> </span>Two other philosophers have developed views in a similar spirit: Lewis Beck, “Extraterrestrial Intelligent Life,” Presidential Address, American Philosophical Association, December 1971 (Reprinted in the <i>APA Proceedings</i>, 1971, pp. 5-21); and Nicholas Rescher, “Extraterrestrial Science,” Chapter 11 of his <i>The Limits of Science</i>, University of California Press, 1984, pp. 174-205.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1329539a9803aefb__ednref3" name="1329539a9803aefb__edn3" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[3]</span></span></span></span></a> See, for example, C. Sagan, <i>Communication with Extraterrestrial Intelligence</i>, op. cit.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1329539a9803aefb__ednref4" name="1329539a9803aefb__edn4" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[4]</span></span></span></span></a> L. Margulis, <i>Symbiosis in Cell Evolution</i>, W.H. Freeman Co, 1981.<span> </span>Symbiosis is a plausible way for complexity to arise, but it need not be the only way.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1329539a9803aefb__ednref5" name="1329539a9803aefb__edn5" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[5]</span></span></span></span></a> See also S.J. Gould, “SETI and the Wisdom of Casey Stangel, in his book <i>The Flamingo’s Smile</i>, Norton, 1985.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1329539a9803aefb__ednref6" name="1329539a9803aefb__edn6" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[6]</span></span></span></span></a> New findings suggest that proto-eyes are very ancient and thus that instead of convergence we have here a case of common ancestry.</p> </div> </div> </div></div>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-11169257352454371842011-09-03T01:02:00.000-07:002011-09-03T22:44:16.101-07:00THE PRINCIPLE OF MEDIOCRITY<div id=":88" class="ii gt"><div id=":89"> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><b><span style="color:black;">CHAPTER 8C</span></b></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><b><span style="color:black;"> </span></b></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><b><span style="color:black;">THE PRINCIPLE OF MEDIOCRITY</span></b></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color:black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color:black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color:black;">Even apart from the wisdom of making contact, we have seen why assuming the principle of mediocrity serves the opponents of SETI well.<span> </span>SETI depends on the possible transmission of signals by extraterrestrials. That is the extent of the search: To listen to the universe with radio telescopes in the hope that an artificial combination of pulses may be identified.<span> </span>And then, of course, we would try to decipher such a signal and perhaps to respond, thereby initiating the most extraordinary communication in the history of the human species. That is the program of SETI. Now, to show the urgency of the matter, the principle of mediocrity is invoked: There may well be a whole club of civilizations out there, and with just a little effort we might be able to join them.<span> </span>But if we assume the principle of mediocrity very literally, and consider the age of the galaxy, we must wonder why the extraterrestrials are not here.<span> </span></span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color:black;"><span> </span>Quite apart from such concerns, this principle deserves examination. Let us begin with the motivation for invoking it. What could we have learned from the Copernican revolution in the first place?<span> </span>Surely not that we are average.<span> </span>At best that we had no reason to assert that we are special. This is not the same as to say that we are not special, for it may well turn out that we are, even if we have no reason at this time to think so.<span> </span>I may have no reason to assert that the respectable looking man walking by my window is a criminal, even though perchance he might indeed be one. At most, then, we should simply gain a healthy skepticism about claims of human privilege.<span> </span></span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color:black;"><span> </span>Moreover, although we have now reasons to believe that the sun is an average star and that the Earth is not the center of the universe, we cannot say that we have similar reasons about our own standing in the realm of life.<span> </span>In the one relevant aspect--intelligence--we are clearly not average in the domain that we have been able to observe. </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color:black;"><span> </span>The principle of mediocrity is prompted, I suspect, by the notion that our belief that the Earth was the center of the universe and that we were the pinnacle of creation sprung from some primitive anthropocentric view of the world later reinforced by religion. Remove the notion of man at the center of things, and it becomes imperative to face up to our average nature.<span> </span>But however convenient for their religion, our ancestors did have good reasons for thinking that the Earth was the center of the universe.<span> </span>It took a lot of ingenuity and good timing to overcome devastating objections to the idea of the motion of the Earth (cf. the treatment of the Tower Argument in Chapter 3).<span> </span>Nor did they think that the Earth was at the center of the universe because it was special in any commendable way.<span> </span>On the contrary, the heavens were eternal, and unchanging, our example of perfection.<span> </span>Change and corruption could take place only in the lowly Earth.<span> </span>Copernicus himself resurrected the Pythagorean claim that the sun should be at the center of the universe since it was obviously so much nobler a body than the Earth.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color:black;"><span> </span>The existence of extraterrestrial intelligence should thus be discussed without the burden of the principle of mediocrity.<span> </span>On the other hand, the principle of mediocrity cannot be used by the opponents of SETI either. The arguments against ETIs can no longer assume that if there are any, they should be so strikingly similar to us that we can make reliable, quasi-probabilistic guesses about them based on intuitions about ourselves. To be acceptable, the arguments must include a wide range of considerations from biology and space science. With this in mind, we need to explore two questions at both ends of the issue. First:<span> </span>how is it possible that ETIs exist but we have no evidence for them?<span> </span>As we have seen, the answer to this first question is that ETIs may exist without our knowing about them. And second: what events or processes could make it possible for our technological civilization to be the only one in the galaxy?</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color:black;"><span> </span>But before we embark on the task of answering this second question, it is useful to cast a critical eye on some practices that reflect on the field of SETI.<span> </span>One of them is the use of what some proponents of SETI call "subjective probability," which they think it permits them to arrive at their rosy conclusions about the chances for the existence of ETI.<span> </span>According to T. Fine, the subjective interpretation of probability "maintains that probability statements are derived through a largely unassisted process of introspection and are then applied to the selection of optimal decisions or acts."<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1322e4a4ad316f83__edn1" name="1322e4a4ad316f83__ednref1" title=""><span><span><span><span style=";font-family:";font-size:12pt;color:black;" >[1]</span></span></span></span></a> Furthermore this subjective view "encourages the holder to fully use his informal judgment, beliefs, experience in arriving at probability estimates."<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1322e4a4ad316f83__edn2" name="1322e4a4ad316f83__ednref2" title=""><span><span><span><span style=";font-family:";font-size:12pt;color:black;" >[2]</span></span></span></span></a> Although personal, such estimates are presumably not arbitrary because "there are reasonable axioms of internal consistency between assessments and constraints that force the user to learn from experience in a reasonably explicit way."<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1322e4a4ad316f83__edn3" name="1322e4a4ad316f83__ednref3" title=""><span><span><span><span style=";font-family:";font-size:12pt;color:black;" >[3]</span></span></span></span></a> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color:black;"><span> </span>This view of probability, together with the principle of mediocrity, has indeed encouraged some SETI enthusiasts to make highly optimistic pronouncements about the likelihood of planets with life, intelligence and technological civilizations, based on the fact that the Earth has life, intelligence and a technological civilization.<span> </span>But can these scientists justify what amounts to giving a statistical distribution from only one case? <span> </span></span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color:black;"><span> </span>If I think it is likely that I will survive intact a jump from the Golden Gate Bridge because I cannot believe that harm can come to me at this stage of my life, my estimate will be as wrong as it is arbitrary.<span> </span>Nonetheless the constraints of the experience (serious injury or death) will most definitely be inconsistent with my assessment.<span> </span>And if I do survive, such inconsistency will force me to learn a valuable lesson. <span> </span>Even so the arbitrariness of my initial assessment is not thereby removed.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color:black;"><span> </span>The intuition behind subjective probability is that a scientist who has already learned from experience, and who is in a situation to which his expertise is relevant, may come up with reliable hunches as to what is the right action to take.<span> </span>Indeed we may measure such probability by determining how much he is willing to bet on a course of action over its alternatives.<span> </span>I think that this notion of probability has serious problems even under the best of circumstances.<span> </span>But in any event it does not apply in the case of SETI.<span> </span>On this subject we have learned nothing from experience because we have had no experience to learn from, nor can we use our expertise about the Earth because our theories are not yet developed enough to make decent guesses about how representative the Earth is.<span> </span>In a few years we are likely to, if we continue to increase the sophistication of telescopes in orbit.<span> </span>We may begin by detecting terrestrial planets at the right distance from their suns to have liquid water; and then we might be lucky enough to find one or more such planets with the right spectrum in their atmosphere (e.g., appropriate percentages of oxygen, methane, etc.) to make us believe that we have detected the “signature” of life.<span> </span>But so far we do not quite have instrumentation that refined.<span> </span>And we do not know if, once we have it, we will ever find such planets.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color:black;"><span> </span>A related misuse of probability comes in the practice of splitting the difference.<span> </span>The optimist will use his subjective probability to estimate that in every mature planetary system there will be at least one planet with life (the probability of life is one), the pessimist will say that the probability is zero because life could have arisen only on Earth.<span> </span>And then there are those congenial types who declare that the truth must fall somewhere in between, and so decide that a probability of one half (or one fourth or one sixteenth) is a "conservative" or "reasonable" estimate. </span></p> <p class="MsoNormal"><span style="color:black;"><span> </span>Imagine, however, that I am given a photograph of a building that could be either Fort Knox or an empty warehouse, and that I am asked to estimate how much wealth that building contains.<span> </span>Suppose that I know that there are 200 billion dollars in gold in Fort Knox.<span> </span>And now, since I have no idea which building it is, I split the difference and estimate that there are 100 billion dollars in it.<span> </span>Whichever building it turns out to be, my estimate will be off by 100 billion, not a small mistake. In the case of ETI our estimates of probability should be based on our knowledge of the universe, not on reaching a compromise between the uneducated guesses of interested parties. As space science advances, we will have more insightful things to say about the chances for extraterrestrial life.<span> </span>For extraterrestrial intelligence we will have to take a few additional steps.</span><span>
<br /></span></p><p class="MsoNormal"><span> </span>To see what those steps are, in the next posting I will discuss briefly the second question listed above: What events or processes would make it possible for our technological civilization to be the only one in the galaxy?<span> </span></p> <div>
<br /><hr align="left" size="1" width="33%"> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1322e4a4ad316f83__ednref1" name="1322e4a4ad316f83__edn1" title=""><span><span><span><span style=";font-family:";font-size:10pt;" >[1]</span></span></span></span></a> T. Fine, “Nature of Probability Statements in Discussions of the Prevalence of Extraterrestrial Intelligence,” in C. Sagan, <i>Communication with Extraterrestrial Intelligence</i>, The MIT Press, 1973, p. 360</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1322e4a4ad316f83__ednref2" name="1322e4a4ad316f83__edn2" title=""><span><span><span><span style=";font-family:";font-size:10pt;" >[2]</span></span></span></span></a> Ibid.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1322e4a4ad316f83__ednref3" name="1322e4a4ad316f83__edn3" title=""><span><span><span><span style=";font-family:";font-size:10pt;" >[3]</span></span></span></span></a> Ibid.</p> </div> </div> </div></div>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-60414702948379062082011-08-27T23:25:00.000-07:002011-08-27T23:26:46.539-07:00Exploration of the Galaxy by Living Beings<div id=":8r" class="ii gt"><div id=":8s"> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><b><span style="color: black;">Chapter 8b</span></b></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><b><span style="color: black;"> </span></b></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><b><span style="color: black;">Exploration of the Galaxy by Living Beings </span></b></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;">This, of course, assumes that interstellar flight is possible. As we already saw, one problem with interstellar flight is that it takes a very long time. Even traveling close to the speed of light, it takes four years to get to the nearest star and over 30,000 years to arrive at the center of the galaxy.<span> </span>As we discussed in Chapter 7, these are not the times for the travelers themselves, who might be able to make a round trip to the center of the galaxy in their lifetimes.<span> </span>Unfortunately the energy involved may be such as to make prohibitive any more than an occasional probe.<span> </span>We have also seen that some extremely fanciful ideas, including ramjets driven by nuclear catalytic engines, and even superluminal starships, are consistent with current physical theory.<span> </span>Nevertheless, we cannot base an impossibility proof on technologies that are at best problematic, for an impossibility proof with weak links is not much of a proof (the same reasoning would apply with even greater force to the development of hyper-space travel, or some of the other fanciful inventions of science fiction writers).<span> </span></span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Still, a velocity 1/100 that of light is within the scope of the technology described in Chapter 7.<span> </span>At this velocity, it would take us about eight million years to arrive at the furthest confines of the galaxy.<span> </span>A more centrally located species could have spread throughout the galaxy in a little over five million years, and that is only a bit more than 1/1000 the age of the Earth.<span> </span>Since the galaxy is at least twice as old as the Earth, if technological civilizations are as prevalent as the proponents of SETI would have it, many such civilizations should have arisen before ours. But that presumably means that they should have been here already.<span> </span>Even at a much lower rate of expansion, the time it takes to cover the entire galaxy is not much compared with the age of the galaxy itself.<span> </span>Our ancestors who migrated from Africa to the rest of the world never completed the journey themselves, but, by moving a little in each generation, eventually they covered the entire planet.<span> </span>And as long as the journey was, it took but a moment in the life of the homo-sapiens family.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Of course, a journey of eight million years for a species that is not yet a million years old would not be a small undertaking, but it is a journey that we may begin one step, one star, at a time. And at any rate, if we realize that complex creatures such as the dinosaurs lived for about 140 million years, and that moving into the cosmos would probably enhance the long-term survival of the species, we can see that the travel time may be relatively short for some species.<span> </span>Presumably this would make a complete expansion by someone or other seem almost inevitable.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>There is no question that interstellar travel at that velocity would pose a variety of social difficulties for us.<span> </span>Chief among them is that it would take 400 years to arrive at the nearest star, perhaps 100 years with improvements in technology. Since it would be a second or third generation that would finish the trip--and if the nearest stars are not suitable, it would take an even later generation--we are not sure that we can entrust the success of the exploration to people that would not have been born when the decision to explore the galaxy is made.<span> </span>It may also be frightfully expensive to keep alive and healthy the many humans that would be necessary to send in a mission of that sort.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Nevertheless, we can cook up several scenarios in which the social obstacles are overcome and a species begins to migrate to the stars: an authoritarian regime forces the issue, or there is forewarning of a cosmic catastrophe, or the migration is simply a natural consequence of a long and massive colonization of the species' own planetary system. In such a case, this version looks more like the impossibility proof it is purported to be.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Moreover, a proponent of SETI cannot reply by bringing up reasons why a civilization may not choose to travel throughout the galaxy.<span> </span>Given that we are average, we can easily imagine why at least one of the many technological civilizations would eventually venture out with the purpose of colonization. This is easy to imagine because we can imagine why we ourselves might begin such an adventure. Accepting low odds (in the style of SETI proponents), let us say that it is one of a thousand options we have. Under certain conditions it may become the most reasonable option.<span> </span>Out of 1,000 advanced civilizations 100 million years ago, then chances are that one would have built starships.<span> </span>But where are they?<span> </span>As for the assumption of expansionism, again from our own case we know that we have a tendency to move onto new niches. Even if the tendency is not overwhelming, the existence of many civilizations will make it likely that at least one will act on it.<span> </span>And all it takes is one, as long as we assume that star travel is indeed possible and that the tendency to expand will give such a civilization the required persistence.<span> </span>The mediocrity principle supports this impossibility proof.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Of course, as in the previous impossibility proof, we may be able to find excuses for why we have not detected an alien presence in our solar system.<span> </span>Imagine for example, the enormous difficulty that we would have ourselves in trying to spot even a large starship that came within a few astronomical units from Earth, a distance that may be quite suitable for an alien species to conduct a survey of our solar system.<span> </span>At that sort of distance it is not easy to detect asteroids smaller than a kilometer across, even when we are searching for them.<span> </span>A starship may come in no closer than Saturn but send much smaller probes into orbit around the other planets.<span> </span>Their advanced stealth systems may be beyond our technological ability to detect.<span> </span>Or the ship may have been here already and gone home (or gone silent).<span> </span>The excuses may be limited only by our imagination.<span> </span></span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>In addition, in this discussion we have to assume that a slower conquest of the galaxy will not be hampered by lack of resources. <span> </span>But once again the Principle of Mediocrity comes to the rescue of the objection. <span> </span>In our own solar system it seems that the Kuiper Belt and the Oort Cloud would offer the resources needed for the survival of a civilization not unlike that envisioned by O’Neill’s in his proposal of space colonies. <span> </span>And since we are pretty much average, we should expect such resources to be spread throughout the galaxy.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>As we will see below, the Principle of Mediocrity makes for an interesting philosophical target.<span> </span>But let us consider first whether seeking contact with advanced alien civilizations is wise.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><i><span style="color: black;">The Wisdom of Contact</span></i><span style="color: black;"></span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;">To make matters worse for SETI, if by some quirk of fortune we have not been found yet, the principle of mediocrity should lead us to question the wisdom of trying to communicate.<span> </span>It is clear that in our complete expansion in our own planet we have done our best to eliminate all significant competition from other species. The last thing we wish to do is advertise our presence to more advanced species who may then wish to occupy our niche, and in the process may need to get rid of the local pests, or at least bring them under control.<span> </span>In some circles there is the feeling that advanced creatures must somehow be wise and benevolent, although under the guidance of the principle of mediocrity it would be difficult to see why. In the first place we have a history of ruthlessness toward species that become obstacles to our aims; we have been ruthless even to other human cultures.<span> </span>Consider for example, as Ron Bracewell has pointed out, what the response of suburbanites might be if raccoons became much smarter.<span> </span>They would be such pests that suburbanites would go to great lengths to wipe them out<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1320eff2b10b4c69_1320efe086ccf4f0__edn1" name="1320eff2b10b4c69_1320efe086ccf4f0__ednref1" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[1]</span></span></span></span></a>.<span> </span>And few of us would lose much sleep over that.<span> </span>Indeed when we try to poison cockroaches and rats, or hunt the coyotes that prey on our sheep, the issue of benevolence or malevolence seldom comes up. </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>In light of these considerations, some suggest that we should lay low until we are in a better position to do battle if need be.<span> </span>There are others who argue that the issue is moot since we have been radiating into space our radio and television signals for a long time.<span> </span>That may be so, but those signals would be very weak and well scrambled by the time they leave the solar system, and in view of the difficulties we have recognized in trying to look for alien transmissions, and the low powers of most of our own transmissions, it is not unreasonable to suppose that detecting life on Earth from, say, 100 light years away would involve a rather substantial amount of luck.<span> </span>Of course, some transmissions, radar beams for example, are very powerful.<span> </span>And in any event, the great activity in the radio range alone might indicate to another civilization that a relatively advanced technology exists here.<span> </span>At the present time the SETI program (not longer at NASA, as I mentioned earlier) does not transmit any messages.<span> </span>There does not seem to be much harm in listening, anyway, and so officially the wisdom of communication is not yet a problem we must face.<span> </span>Nevertheless, unofficially we do have to concern ourselves with it, since some radio astronomers have already sent messages on their own. </span></p> <p class="MsoNormal"> </p> <div>
<br /> <hr align="left" size="1" width="33%"> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1320eff2b10b4c69_1320efe086ccf4f0__ednref1" name="1320eff2b10b4c69_1320efe086ccf4f0__edn1" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[1]</span></span></span></span></a> R. Bracewell. <i><span style="font-size: 10pt;">The Galactic Club</span></i><span style="font-size: 10pt;">. San Francisco: W. H. Freeman 1975.</span></p> <p> </p> </div> </div> </div></div>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-38857370962739600812011-08-19T23:42:00.000-07:002011-08-19T23:49:36.901-07:00THE SEARCH FOR EXTRATERRESTRIAL INTELLIGENCE<p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><b><span style="color: black;">CHAPTER 8a </span></b></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><b><span style="color: black;"> </span></b></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><b><span style="color: black;">THE SEARCH FOR EXTRATERRESTRIAL INTELLIGENCE</span></b></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;">Are we alone in the universe? Is it really possible that no sentient being on a faraway planet ever contemplated the stars and felt awe?<span> </span>That only humans ever wondered about the nature of the universe, or pondered whether similar beings might be asking similar questions? In the view of some people it is extremely parochial to suppose that we are alone – one more instance of the syndrome that once made us believe that the Earth was the center of the universe.<span> </span>According to those people, we have no more reason now to believe that we must be the pinnacle of creation than we had once upon a time to believe that the Earth was so special.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Thus begins the reasoning that takes them to the conclusion that extraterrestrial intelligences (ETI) are likely to exist, a presupposition without which the search for them (SETI) would make little sense. This does not mean, however, that the proponents of SETI advocate the building of starships at all.<span> </span>Indeed, many of its practitioners believe that star travel is not very likely, at least not for a very long time.<span> </span>They urge instead that we scan the skies for the radio signals of other advanced species. </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Success in their mission is seen by SETI proponents as of such extraordinary importance that at some point they proposed Project Cyclops, a very elaborate, and expensive, arrays of radio telescopes to carry it out.<span> </span>Their proposals were not received with much sympathy by those who control the purse strings, and thus over the years they had to content themselves with ever meager levels of support (from tens of billions for the proposed Cyclops<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131e5c3796cb95b7_131e5b2d2d44b602__edn1" name="131e5c3796cb95b7_131e5b2d2d44b602__ednref1" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[1]</span></span></span></span></a> to less than two million per year in actual funding, and then to nothing).<span> </span>But what seemed like a deplorable situation to them appeared far too exorbitant to opponents of SETI.<span> </span>For in the view of such opponents, the very foundation of SETI, that extraterrestrial intelligence probably exists, was not only unwarranted but preposterous.<span> </span>U.S. Senator William Proxmire gave the program his Golden Fleece Award, for the most inane waste of taxpayers’ money.<span> </span>Eventually NASA cut SETI of its budget altogether.<span> </span>But the program lives on, bolstered by the privately-funded SETI Institute and by the ingenuity and good will of many contributing scientists. </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Ironically, the opposition to SETI is buttressed by the key assumption of the SETI proponents themselves: Carl Sagan’s so-called "Principle of Mediocrity."<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131e5c3796cb95b7_131e5b2d2d44b602__edn2" name="131e5c3796cb95b7_131e5b2d2d44b602__ednref2" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[2]</span></span></span></span></a><span> </span>The <i>Principle of Mediocrity</i> asserts that the sun is a typical star in having a planet like the Earth in which life could arise, that terrestrial life is typical in having produced intelligence, and that human intelligence is typical in giving rise to a technological civilization. </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span></span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>Presumably Copernicus taught us humility when he argued that the Earth was not privileged but average, and later astronomy reinforced the lesson by discovering that the sun itself was merely an average star in an average galaxy.<span> </span>By extending the Copernican lesson, the reasoning goes, we should learn to be humble about our own position in the scheme of life. The principle of mediocrity thus purports to recognize that humanity and the conditions that have brought it about are pretty much average.<span> </span>In their arguments, the <i>opponents</i> of SETI stretch this principle slightly to add that a technological civilization is typically expansionist.<span> </span>As a result they are able to produce a variety of "impossibility proofs" against the existence of extraterrestrial intelligence.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span></span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span>In the pages that follow I will examine the justification of SETI in light of this controversy. This examination, I trust, will lead naturally to a discussion of some of the important philosophical assumptions made by SETI in estimating our ability to communicate with ETIs if they exist, a very interesting issue in its own right.<span> </span>Let me begin with a brief account of the reasons for optimism with respect to SETI.<span> </span>I will then proceed with an explanation of how such optimism actually sets up the impossibility proofs.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;">MOTIVATION FOR SETI</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;">First there is the incredibly large number of stars.<span> </span>This galaxy alone contains over 100 billion, and there may be at least 100 billion galaxies.<span> </span>We do not know how many of those stars have planetary systems, but most theories of star formation would encourage us to believe that planets are rather common, at least in the average stars of what is called the Main Sequence (of star evolution) such as our own Sun.<span> </span>As we saw in Chapter 5, this optimism has been born out by the recent discovery of over 200 Jupiter-planets and a few rocky (“terrestrial”) planets around other stars, as well as by the very credible evidence for forming planetary systems around young stars.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span></span>All this has some very convenient aspects for SETI.<span> </span>One is that the average stars may live longer than ten billion years.<span> </span>Since it has taken about four and half billion years to produce a technological civilization on this planet, it is encouraging to know that the stars that live long enough are also the ones most likely to have planets in the first place.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span>
<br /></span></span></p><p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span></span>From here on matters generally become far more speculative. Those who are in the business of making probability estimates for SETI often use the so-called "Drake Equation" (named after Frank Drake, the contemporary astronomer who first proposed it).<span> </span>According to this equation, the number of intelligent civilizations in this galaxy is equal to the product of the rate of star formation, the percentage of favorable stars, the number of planets around such stars, the fraction of Earth-like planets among those, the fraction of such planets in which life begins, the fraction of planets with life in which intelligence develops, and then the number of planets with intelligence in which technological civilizations arise.<span> </span>This product is then multiplied by the average longevity of a technological civilization. </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span></span>We believe that in this galaxy the rate of star formation is about twenty per year. And the existence of other planets is now established, although not the rate of planet formation.<span> </span>But as we progress through Drake's equation, the estimates are not as well grounded. This situation does not prevent SETI enthusiasts from assigning optimistic probabilities to every factor.<span> </span>One often hears, for example, that once life begins on a planet, intelligence is very likely to result eventually.<span> </span>Such optimism surely deserves examination. </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;">Impossibility Proofs: A Summary</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;">The most interesting impossibility proof against the existence of ETIs is the famous question by Enrico Fermi, which assumed an early version of Sagan’s Principle of Mediocrity: “Where are they?”<span> </span>With such good omens for the existence of ETIs, they should be everywhere, including our own solar system, watching us, making contact with us, and so on.<span> </span>But we don’t see them, hear them, or in any other way detect them.<span> </span>This of course assumes also that all the talk about UFOs, alien abductions, and the like is a delusion, or at best an illusion.<span> </span>So, if aliens do exist, they should be all over the place, but we have no trace of them; therefore, they do not exist.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;">SETI proponents like Bernard Oliver, however, argued that the reason we don’t see them is because star trekking takes too long, since the distances between solar systems are so vast.<span> </span>So no one can really be expected to undertake such a trip.<span> </span>That is why we need to resort to electromagnetic signals as a means to search for ETIs, as well as a means for communicating with them if we ever find them.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;">We have seen in the previous two postings why Oliver’s case is not as good as he might have thought.<span> </span>We cannot rule out the possibility of travel between the stars, either by traveling space colonies, or by ships that approach the speed of light. <span> </span>It is also physically possible, as we have seen, that warp engines might actually allow us to go faster than light (cf. Alcubierre<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131e5c3796cb95b7_131e5b2d2d44b602__edn3" name="131e5c3796cb95b7_131e5b2d2d44b602__ednref3" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[3]</span></span></span></span></a>). <span> </span>Nevertheless we cannot affirm it either.<span> </span>This result weakens the impossibility proof some, but not completely: It still manages to cast serious doubt upon the existence of very advanced civilizations.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;">Some opponents of SETI have brushed Oliver’s response aside for a different reason.<span> </span>Even if star trekking takes too long for living things, an advanced civilization could still send self-reproducing machines to report about every interesting solar system, including ours.<span> </span>All they need do is send one.<span> </span>Once it gets to the backyard of another star, it will make copies of itself, which will then move on to other stars and do likewise.<span> </span>This self-reproducing probes will reproduce and cover any galaxy, give or take a few million years, the way a bacteria culture ends up taking over a petri dish. <span> </span>Thus Fermi’s question arises all over again:<span> </span>“Where are they?”</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;">I do not believe that this impossibility proof succeeds.<span> </span>It is based on John von Neumann’s “proof” for the possibility of self-reproducing automata.<span> </span>I make two main points against such proof as the basis for exploring the galaxy in the fashion considered here.<span> </span>The first is that the conditions that make von Neumann’s proof plausible are not likely to be met under the exigencies of exploration.<span> </span>The second is that von Neumann assumes that a genome is like a computer program, and I think that such an assumption is unwarranted.<span> </span>I then criticize some clever proposals to apply von Neumann’s ideas to interstellar exploration (e.g. with space probes based on collections of nanorobots).<span> </span>Unfortunately I will have to ask my readers’ forgiveness for not providing the details of my arguments.<span> </span>As it turns out, such details will appear in my contribution to a book on imaging outer space that will be published in December.<span> </span>I promised the editor, Prof. Alexander Geppert, that I would not post the article, since the publisher would be naturally upset were my chapter to appear in this blog right before the publication of the book.</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;">I will, however, provide a little plug for the book, since it is likely to interest most of you (I do not share in the profits).<span> </span>The title of my chapter is “Self-Reproducing Automata and the Impossibility of SETI.” <span> </span>The title of the book is Imagining Outer Space, and the editor is Alexander C. T. Geppert, as I said.<span> </span>The publisher will be Palgrave MacMillan</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;">You can find out more information about the volume by clicking on this link:</span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><a href="http://www.palgrave.com/products/title.aspx?PID=364196" target="_blank">http://www.palgrave.com/<wbr>products/title.aspx?PID=364196</a><span style="color: black;"></span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"> </span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;">
<br /></span><span style="color: black;"></span></p> <p class="MsoNormal" style="margin-top: 0in; margin-right: 0.5in; margin-bottom: 0.0001pt;"><span style="color: black;"><span> </span></span></p>
<br /> <hr align="left" size="1" width="33%"> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131e5c3796cb95b7_131e5b2d2d44b602__ednref1" name="131e5c3796cb95b7_131e5b2d2d44b602__edn1" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[1]</span></span></span></span></a> For a descripton of Cyclops see Bernard Oliver’s description in Carl Sagan, ed., <i>Communication with Extraterrestrial Intelligence</i>, MIT Press, 1973, pp. 279-301.<span> </span>The report on the project was published by NASA: CR 11445.</p> </div> <div> <p class="MsoNormal"><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131e5c3796cb95b7_131e5b2d2d44b602__ednref2" name="131e5c3796cb95b7_131e5b2d2d44b602__edn2" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[2]</span></span></span></span></a> <span style="font-size: 10pt;">Carl Sagan, <i>Pale Blue Dot</i>, Random House, 1994, pp. 39, 372-73.</span></p> </div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131e5c3796cb95b7_131e5b2d2d44b602__ednref3" name="131e5c3796cb95b7_131e5b2d2d44b602__edn3" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[3]</span></span></span></span></a> It seems that I left out the reference to Alcubierre’s seminal paper in my previous posting.<span> </span>It is as follows: Miguel Alcubierre (1994): "The Warp Drive: Hyper-Fast Travel within General Relativity". <i>Classical and Quantum Gravity</i>, 11: L73-L77.</p> Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-70084642941800838302011-08-15T00:18:00.000-07:002011-08-15T00:20:53.990-07:00Faster-Than-Light Starships<div id=":5d" class="ii gt"><div id=":65"> <p class="MsoNormal"><b>Chapter 7F</b></p> <p class="MsoNormal"><b>Faster-Than-Light Starships</b></p> <p class="MsoNormal"> </p> <p class="MsoNormal">The second fantastic proposal is even more interesting from the theoretical point of view. <span> </span>I am referring now to the prohibition that the special theory of relativity places on attempts to <i>reach and surpass</i> the speed of light.<span> </span>A way around this prohibition may be to move beyond the special theory. The basic intuition behind this idea is as follows: The speed barrier applies within the special theory of relativity, which requires the formula for addition of velocities we have seen above, and which presupposes non-accelerated frames.<span> </span>But does it have to hold within the accelerated frames of the general theory of relativity, or within a theory of quantum gravity?<span> </span></p> <p class="MsoNormal"><span> </span>Indeed the suggestions that have aroused the greatest interest in the last twenty years or so concerning travel faster than light both make use of the General Theory.<span> </span>I will discuss briefly two of them, the most interesting two.<span> </span>Please keep in mind, however, that at this stage the goal of the discussion is not to determine which of these suggestions is more likely to take us to the stars in faster-than-light starships, but whether physical theory permits traveling faster than light.</p> <p class="MsoNormal"><span> </span>The first suggestion is Kip S. Thorne’s idea to use a Wheeler quantum wormhole to travel in a very short time to places that in normal spacetime could be thousands or even millions of light years away<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__edn1" name="131cbacf3c10ffba__ednref1" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[1]</span></span></span></span></a>.<span> </span>Imagine that space time is folded (for example in a fifth dimension in addition to the three of space and the one of time).<span> </span>That fold may bring close together, in that fifth dimension (or in so called “hyperspace”), regions of space that are extremely far from one another in the normal three space dimensions.<span> </span>It is as if we took a long cloth and brought close together the two ends.<span> </span>If the cloth were laid flat the two ends might be separated by a distance of one meter, but now that we have folded the cloth, the two ends might be only, say, a millimeter apart.<span> </span>If we could only make a little tube that connected them across that millimeter, the trip from end to end would be far shorter. John Archibald Wheeler’s proposed that, in extremely small regions (around a Planck length, 1x10<sup>-33</sup> cm), strong gravitational quantum fluctuations create a sort of “quantum foam,”<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__edn2" name="131cbacf3c10ffba__ednref2" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[2]</span></span></span></span></a> in which we might find such a little tube, a “wormhole.” The trick is to find one wormhole in the foam, to enlarge it so a ship can go through it, and then to keep it open so it will not crush the ship.</p> <p class="MsoNormal"><span> </span>Let us consider all three aspects of Thorne’s idea, which he developed upon a request from his friend Carl Sagan.<span> </span>The first problem is to find the wormhole.<span> </span>No one has ever detected one, and we do not even know if they exist.<span> </span>If none exist, or we cannot find them, an alternative would be to create one, as long as wormholes <i>could</i> exist. But can they? Wheeler’s results came from his attempts to construct a theory of quantum gravity. Unfortunately, half a century later we do not yet have an adequate theory on the subject.<span> </span>It is difficult to say then, even if we take Wheeler’s imaginative idea seriously, that physical theory does not forbid faster-than-light travel.<span> </span>The special theory of relativity certainly seems to forbid it.<span> </span>Does Wheeler’s joining of the General Theory and quantum theory somehow bring to light enough evidence to show some limitations to the special theory? It might if it were true, but that is precisely what we do not know.</p> <p class="MsoNormal"><span> </span>Since we do not have an acceptable theory of quantum gravity, we are simply in a state of ignorance.<span> </span>From that ignorant perspective, travel faster than light may or may not be permitted by the laws of the universe (which we do not really know).<span> </span>The situation would be similar to asking in, say, 1855, whether it is possible in principle for a ship to travel at 300.000 Km/s. Nothing would seem to forbid such a feat, but only because Einstein’s formula for the relativistic addition of velocities was still 50 years away from appearing in print. Some may believe that the situation is actually worse, since we have no trustworthy theory to give us even seemingly reliable guidance – in 1855 we had Newton’s.</p> <p class="MsoNormal"><span> </span>Some reason for optimism comes from the Casimir effect, which demonstrates that the vacuum is indeed teeming with virtual particles coming in and out of existence, as we would expect in Wheeler’s account. Cassimir suggested in 1948 that if two metal plates were placed micrometers away from each other in a vacuum, and in the absence of an electromagnetic field, some virtual photons would not appear between them because of their long wavelengths. In that case, there would be a greater density of virtual photons outside the plates than between them.<span> </span>This difference in density would result in pressure being applied to the plates from the outside, and thus they would move towards each other.<span> </span>The confirmation of the Casimir effect in 1958 is strong evidence for the hypothesis that virtual particles are prevalent in the vacuum, and many now see it as confirmation also that there is some sort of spacetime foam a la Wheeler.<span> </span>Notice, however, that the Casimir effect seems accounted for within quantum theory and is, at the very least, neutral about possible interactions between gravity and quantum effects.</p> <p class="MsoNormal"><span> </span>Suppose, however, that we do find or create a Wheeler wormhole.<span> </span>Unlike the wormholes that might exist as a result of black hole singularities (in which the matter that disappears into the singularity “tunnels out” to another universe or another part of the universe, and in which the tunnel would close too quickly and the extraordinary gravity would crush any would-be traveler), Wheeler wormholes would be extremely small, of Planck dimensions.<span> </span>It would be necessary to make them longer, so as to connect one of the entrances with some desirable destination, and wider and stable, so we could send our astronauts through them.<span> </span>How could this be accomplished?<span> </span>The favorite answer: exotic matter.<span> </span>Now exotic matter is truly exotic.<span> </span>Presumably it would have negative mass, or at least exert negative energy (it would push the walls of the wormhole outward).<span> </span>And of course we have no idea whether it could exist.<span> </span>But Thorne and his coworkers think that something like the Casimir effect might produce negative energy inside the wormhole to keep it open.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__edn3" name="131cbacf3c10ffba__ednref3" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[3]</span></span></span></span></a></p> <p class="MsoNormal"><span> </span>Think back, however, to the description of the Casimir effect given above.<span> </span>If we think of the vacuum as having zero energy, then we could think of the volume between the metal plates as having negative energy.<span> </span>It is a relative assignment of sign given the description we choose.<span> </span>But it does not seem sensible to say, for example, that the virtual particles within that volume have negative mass, or anything of the sort.<span> </span>Those photons have no peculiar properties compared to the virtual photons outside of the plates. So it is not as if we could go looking for some exotic matter to spoon into the wormholes. But perhaps what Thorne is after is what he calls “exotic fluctuations,” which would create negative energies, and which Hawking presumably showed existed at the event horizon of a black hole.<span> </span>Such exotic fluctuations would account for Hawking’s radiation.<span> </span>Nevertheless, a less exotic description is that the black hole pulls a member of a virtual particle pair inside the horizon while letting the other member escape into the universe, thus creating a glow of energy around the event horizon.<span> </span>We may then say that this positive energy is compensated by negative energy being sucked into the black hole (again a relative assignment of sign).</p> <p class="MsoNormal"><span> </span>In any event, to expand a wormhole’s diameter along these lines, it would seem that a great deal of energy would have to be concentrated into the small region of the mouth of the wormhole so as to create a pronounced spacetime curvature in that region.<span> </span>Whether this would really lead to the desired opportunity for faster-than-light travel would have to be determined by a good theory of the interaction of gravity and quantum phenomena.<span> </span>If we only had one.</p> <p class="MsoNormal"><span> </span>Of course, some of these theoretical ideas may turn out to be correct.<span> </span>Perhaps new experimental work that concentrates large energies into small regions could confirm the existence of spacetime foam, wormholes, and exotic matter (or at least some way of bringing about something akin to the Casimir effect inside a wormhole).<span> </span>But until such a time we will not really be in a position to say that travel faster than light is possible.</p> <p class="MsoNormal"><span> </span>Imagine, nevertheless, that we do find or create a Wheeler wormhole, expand it and ensure its stability.<span> </span>We are still faced with a major conceptual difficulty: an outcome of travel through the wormhole is that an astronaut would also travel back in time. You may return before you take off! This gives rise to all sorts of puzzles about landing on your infant grandfather and killing him, which would make it then impossible for you to be born and thus to go on the trip in the first place. This absurd consequence would be a possibility in an established wormhole, if we do find one, that is, since it is a possibility in general for travel faster than light, as has been known for a long time.<span> </span>An example I recall from my student days was that if you had a gun that shot tachyon bullets, one such bullet could ricochet off the wall and kill you before you pulled the trigger (tachyons are particles that always travel faster than light, and thus do not violate special relativity since they never accelerate to the velocity of light).</p> <p class="MsoNormal"><span> </span>Thorne offers an interesting illustration of time travel in a manufactured wormhole.<span> </span>He imagines making a short wormhole with one mouth in his living room and the other in a starship sitting just outside on his lawn.<span> </span>His wife takes off in the starship traveling at close to the speed of light. Obviously, the two mouths of the wormhole have different times, once her trip begins, as measured in a framework outside of the wormhole, although inside the wormhole the times remain the same. Thorne’s wife returns some hours later (her ship time), although years have gone by on Earth.<span> </span>She has two choices.<span> </span>She can meet Thorne on the lawn upon the landing of the ship and notice how much he has aged.<span> </span>Or she can crawl back using the wormhole to a time <i>before</i> she left on her space journey. Of course, she would then meet her own old self getting ready to go on her space journey.<span> </span>And of course, accidents could happen that would prevent her old self from starting that journey.</p> <p class="MsoNormal"><span> </span>These paradoxes make travel back in time conceptually absurd, which makes this type of faster-than-light travel also conceptually absurd.<span> </span>But could the paradoxes be resolved?<span> </span>One suggestion is that unknown laws of quantum physics (or quantum gravity, or who knows what) prevent anyone, or anything, to travel to the past and create impossibilities (it is impossible to go back and kill your grandfather if you were never born because you killed him when he was an infant).<span> </span>This possibility is not only ad hoc but mere wishful thinking<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__edn4" name="131cbacf3c10ffba__ednref4" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[4]</span></span></span></span></a>.<span> </span></p> <p class="MsoNormal"><span> </span>Another is that the astronauts traveling through a wormhole would not create any inconsistent “time loops” because they would actually end up in an Everett alternative universe (according to Everett, each of two possible alternative quantum states is real, although each is real in a different historical line (or world, or parallel universe).<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__edn5" name="131cbacf3c10ffba__ednref5" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[5]</span></span></span></span></a><span> </span>So you would not really land on your grandfather, you would land on your grandfather’s equivalent in a different historical line.<span> </span>It is difficult to distinguish this physics from science fiction, but even a less cynical appraisal of this possibility should let us see that we are no longer talking about going to the past but rather to a different dimension or universe that is almost like your past and landing (and killing) someone who is exactly like your infant grandfather.<span> </span>It is also obvious that you never arrive at your destination, but at a planet around a star that is exactly like the one you were trying to reach, except for being located in another dimension or universe. And it seems that one should expect similar dislocation on the return trip; that is, you can never come home.<span> </span>Wormholes appear to be problematic enough without combining them with Everett’s interpretation of quantum mechanics.</p> <p class="MsoNormal"><span> </span>A third suggestion is that there are indeed many worlds, more or less a la Everett, but that some are destroyed by inconsistent “time loops.” Our world exists because no one has killed his grandfather, etc., in any travel to the past.<span> </span>Time-travel consistency would function as a selection factor for possible worlds.<span> </span>The problem is, however, that when time travel alters the past it destroys a history that could be tens, hundreds, thousands, millions, or billions of years long.<span> </span>We do not know from when the fatal time traveler is going to come.<span> </span>Moreover, he may arrive tomorrow at noon, or a million years ago.<span> </span>And we would no longer be.<span> </span>In fact, in the second scenario, we would no longer <i>have been</i>.<span> </span>This suggestion does not seem to work well as a solution to the paradox.</p> <p class="MsoNormal"><span> </span>Thorne proposes an apparently more sensible approach.<span> </span>He discovered that some round-trip trajectories through a wormhole may be perfectly consistent: a billiard ball may return and hit itself a glancing blow that will still permit its earlier version to go on the trip.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__edn6" name="131cbacf3c10ffba__ednref6" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[6]</span></span></span></span></a> Presumably, since this loop is causally consistent, we no longer face a paradox. Paul Davies seems to agree and provides an interesting variant: A rich man travels back in time, meets his (young) grandmother and unwittingly gives her information about stock prices in her future.<span> </span>She invests her money using that information, which leads to immense wealth for her and for her grandson. Davies claims that “[N]o paradox ensues here.”<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__edn7" name="131cbacf3c10ffba__ednref7" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[7]</span></span></span></span></a> Surprisingly he finds paradox in a case essentially alike. A professor travels to the future, finds a mathematical formula in a book, returns to his time and gives the formula to a student, who then publishes it.<span> </span>That is the publication that the professor reads many years later. But neither the professor nor the student created the formula.<span> </span>Thus information has come from nowhere, or rather just from the time travel.<span> </span>In the earlier case the grandmother could not have created her fortune (or the student written the paper) without the foreknowledge made possible by the relevant time traveler (grandson, professor).<span> </span>Because the association between information and entropy, Davies thinks that this “free” information is “equivalent to heat flowing backward from cold to hot.”<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__edn8" name="131cbacf3c10ffba__ednref8" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[8]</span></span></span></span></a> </p> <p class="MsoNormal"><span> </span>It seems to me that the situation is even more dire than that.<span> </span>In Thorne’s example a sequence of events, a history, leads to a future event that in turn causes a destruction of that very history and its replacement by another.<span> </span>Something had happened, and now it has not. But if it has not, how could the inconsistent causal loop arise in the first place?<span> </span>Those who have no trouble accepting something like Everett’s many-worlds view, or the even fancier notions of string theory, perhaps are not bothered<span> </span>by this new paradox all that much.<span> </span>But it must be pointed out, as it is generally accepted, that the empirical evidence for the first is scant and for the second non-existent. In Davies’ examples, there is not even an original history to create the conditions for the consistent causal loop: the man is already rich (without his grandmother having made the right investments), the professor already finds the mathematical formula (that no one has really invented). The loop just is.<span> </span>Causality is violated.<span> </span>Jorge Luis Borges would be pleased.<span> </span>But on the basis of such physics we do not have enough to say that faster-than-light travel is possible.</p> <p class="MsoNormal"><span> </span>One point of logic needs to be considered.<span> </span>Even if causally consistent time loops did not fall prey to these objections, it is difficult to see how such loops fix the conceptual absurdity of going to the past.<span> </span>The paradox is not that every time we go to the past we kill our infant grandfather, etc.<span> </span>The paradox is that <i>we could</i>, accidentally or otherwise.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__edn9" name="131cbacf3c10ffba__ednref9" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[9]</span></span></span></span></a><span> </span>Thorne’s proposed solution is that there may be consistent loops.<span> </span>But, the danger still exists that, for example, the rich man’s son, years after his father’s time trip, indeed, years after his father’s death, finds the time machine, pushes the wrong button and ends up landing on his infant great grandmother, crushing her to death.<span> </span>That would make his family’s history, including the presumed consistent causal loop, become non-existent!<span> </span>The paradox has not been resolved.</p> <p class="MsoNormal"><span> </span>One might think that if it is possible for someone from further in the future to annihilate that consistent loop, then that consistent loop was part of a longer but inconsistent loop; but in that case the longer loop itself would have been eliminated, and thus we have nothing to fear from time travel.<span> </span>Therefore we have no paradox.<span> </span>This response might make some sense if we hold to a metaphor of a frozen four-dimensional spacetime (like a vine made up of time slices of the other three dimensions).<span> </span>In that metaphor time is already all laid out and some Cosmic Pruner has cut out all the inconsistent loops from the cosmic vine.<span> </span>This would be as ad hoc as it is convenient. But the universe we experience unfolds in time, and we need a rather long causal sequence of events to create the conditions under which someone can go back to his past to wipe it out.<span> </span>That sequence of events, however, would have no particular marks to distinguish it from the one humans find themselves in already.<span> </span>Since the building of an actual time machine is presumably way in the future, if ever, we would not know whether we are in a real world (because either we will not invent time machines, or if we do the time loops they bring about will all be consistent) or in a world that one unexpected day will no longer <i>have existed</i>.</p> <p class="MsoNormal"><span> </span>No wonder, then, that to save physics from absurdity, Hawking conjectured that the unknown laws of quantum gravity provide chronology protection, that is, that the universe does not allow time machines.<span> </span>This protection, he said, will “keep the world safe for historians.”<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__edn10" name="131cbacf3c10ffba__ednref10" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[10]</span></span></span></span></a></p> <p class="MsoNormal"><span> </span>To say that faster-than-light travel is possible, then, we need to show that we have accepted some relevant theories that permit it, or else we need to point to empirical evidence that, even in the absence of theory, suggest that possibility (e.g. people knew that flight was possible because they saw birds and insects fly, long before they had any theories that explained the flight of birds and insects).<span> </span>One problem with the theories of quantum gravity I have mentioned is that they have not been accepted because the empirical support is not there.<span> </span>I suspect the reason their proponents openly pursue such wild imaginings is that relativity and quantum theory presumably granted physicists the license to make unintuitive claims.<span> </span>Hypotheses about Wheeler wormholes, branes, the multiverse, and the like, it seems, do not sound any stranger today than, say, the wave-particle duality of light and matter did almost a hundred years ago.<span> </span>But I think there is a difference.<span> </span>When Einstein accounted for the photoelectric effect by suggesting quanta of light, his explanation was generally rejected, even by those who used his calculations.<span> </span>Bohr, for example, pointed out that Einstein’s account was contradicted by many experiments that showed clearly the wave nature of light.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__edn11" name="131cbacf3c10ffba__ednref11" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[11]</span></span></span></span></a><span> </span>Eventually Compton’s X-ray scattering experiments made Bohr accept the dual nature of light and this led to his famous principle of complementarity.<span> </span>The moral of the story is that physicists were forced by the phenomena to propose and accept otherwise extremely unintuitive views.<span> </span>Their experiments were their warrant.<span> </span>Perhaps other, more sensible views would have done the job, but no one proposed a persuasive one. Moreover, as I have argued elsewhere, the unintuitive character of their views, at least in the case of the principle of complementarity, was due to the general acceptance of a mistaken epistemology.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__edn12" name="131cbacf3c10ffba__ednref12" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[12]</span></span></span></span></a><span> </span>Einstein’s theory of relativity, although not similarly prompted by experimental results, was nevertheless soon an important tool in contrasting our ideas with the world.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__edn13" name="131cbacf3c10ffba__ednref13" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[13]</span></span></span></span></a><span> </span>None of this is the case with the highly speculative ideas so much in vogue today, and as we have seen, those ideas do not permit us to say whether we will ever be able to go faster than light.</p> <p class="MsoNormal"><span> </span>To rule on that possibility, we need, in addition to the requirements of theory or empirical evidence mentioned above, a way of travel that does not imply going back to the past.<span> </span>A way out of this difficulty is to realize that the speed of light operates as a limit only within the special theory of relativity.<span> </span>But within the general theory we may find ways to travel faster than light without going back in time.<span> </span></p> <p class="MsoNormal" style=""><span style="color: black;"><span> </span></span>Miguel Alcoubierre argued in a paper published in <i>The Journal of Classical and Quantum Gravity</i> in 1994 that, if we built an engine that contracts spacetime in front of the starship, and expands it behind it, we could accelerate the starship to a velocity arbitrarily higher than that of light.<span> </span>Since the local spacetime for the ship would be flat, the astronauts would not violate the relativistic speed limit at any one point in their journey, although, from the perspective of the Earth-bound observers, the ship might be traveling much faster than light.<span> </span>By thus warping spacetime, the ship may make a return trip to Vega, which is 25 light years away, in, say, three or four Earth years, from the point of view of Earth-bound observers, instead of more than fifty, as would be the case under special-relativity considerations. Alcoubierre’s arrangement also has the ship move only into the future, as airplanes and slugs do, and so we do not have to worry about time paradoxes.</p> <p class="MsoNormal"><span> </span>Of course, from this theoretical possibility to building a starship with a “warp” engine there is a long gap.<span> </span>What kind of technology could possibly contract spacetime?<span> </span>Some have suggested strange matter, but we have discussed that enough in this work not to pin our hope on it.<span> </span>We actually do not know what would work.<span> </span>But we do know that spacetime can expand, for that is precisely what dark energy accomplishes.<span> </span>We do not know how dark energy does it, just as we do not know what dark energy is.<span> </span>A hypothesis, however, is that the expansion of spacetime results from some kind of scalar field.<span> </span>To understand how a scalar field works, let us think about a spring that is pulled open until suddenly returns to its original state, or how a rubber ball pressed on all sides suddenly expands.<span> </span>If one takes seriously the suggestion by string theorists that there exist “space atoms,” then one can also imagine that only a limited amount of energy can be held in one of those atoms.<span> </span>Once it reaches the maximum, the energy “bounces” like the rubber of the compressed ball, carrying spacetime with it as it expands<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__edn14" name="131cbacf3c10ffba__ednref14" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[14]</span></span></span></span></a>.<span> </span>But these are all metaphors.<span> </span>What matters is that it happens, that spacetime does seem to expand, even if we cannot explain why.<span> </span>Birds did fly at a time when people could not explain how they could fly.<span> </span>Besides, such expansions, and contractions, of spacetime could be seen as variants of the lambda term that Einstein added to his equations to keep the universe from expanding.</p> <p class="MsoNormal"><span> </span>Perhaps to construct the right kind of machine we may still need an acceptable theory of quantum gravity.<span> </span>For example, to produce the required local expansions and contractions we may use some form of interaction between electromagnetic and gravitational forces in very small volumes.<span> </span>But further speculations along these lines go beyond the intent of this work.<span> </span>What matters is that the desired processes are possible, given Einstein’s theory of general relativity and the existence of dark energy.<span> </span>Theory and experience thus permit travel faster than light, as long as such travel does not include the possibility of traveling to the past.<span> </span>Alcubierre’s proposal accords with the conceptual requirements, although of course there are no guarantees that such a spaceship will ever travel through interstellar space, just as there are no guarantees that we will ever achieve relativistic velocities either.<span> </span></p> <p class="MsoNormal"><span style="color: black;"><span> </span>Whether these technologies will ever come to fruition I do not know.<span> </span>But what seems rather clear to me is that the physical expansion of humankind into the cosmos will vastly enhance our ability to preserve the dynamic character of science, while at the same time making it far more likely that a sun, some sun, will rise on the world of our descendants in a future so distant that most species on the surface of the Earth will have long disappeared.<span> </span>It is the process toward that long expansion that will make it possible to determine whether the relativistic velocities are technologically possible.<span> </span>I can only hope that we will set in motion the events that will ultimately allow our descendants to make that determination if they so choose. </span></p> <p class="MsoNormal"><span style="color: black;"><span> </span>This possibility of continuous expansion offers, then, a double bounty for our species.<span> </span>It increases our chances of survival, as we have seen.<span> </span>And it also preserves for a long time the opportunity to challenge our views of the universe.<span> </span>As Robert Goddard wrote in a letter to H.G. Wells, in 1932, "there can be no thought of finishing, for `aiming at the stars,' both literally and figuratively is a problem to occupy generations, so that no matter how much progress one makes, there is always t</span></p> <div>
<br /> <hr align="left" size="1" width="33%"> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__ednref1" name="131cbacf3c10ffba__edn1" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[1]</span></span></span></span></a> K.S. Thorne, <i>Black holes and time warps: Einstein’s outrageous legacy</i>.<span> </span>W.W. Norton and Company. 1994.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__ednref2" name="131cbacf3c10ffba__edn2" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[2]</span></span></span></span></a> J.A. Wheeler. (1962): <i>Geometrodynamics</i>.<span> </span>Academic Press.</p> </div> <div> <p class="MsoNormal" style="background: rgb(248, 252, 255) none repeat scroll 0% 0%; -moz-background-clip: border; -moz-background-origin: padding; -moz-background-inline-policy: continuous;"><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__ednref3" name="131cbacf3c10ffba__edn3" title=""><span><span style="font-size: 10pt;"><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[3]</span></span></span></span></span></a><span style="font-size: 10pt;"> <b><u><span style="color: blue;">^</span></u></b>Morris, M., Thorne, K. and Yurtsever, U. (1988): <span> </span>“</span><a href="http://prola.aps.org/abstract/PRL/v61/i13/p1446_1" title="http://prola.aps.org/abstract/PRL/v61/i13/p1446_1" target="_blank"><span style="font-size: 10pt; color: black; text-decoration: none;">Wormholes, time machines, and the weak energy condition</span></a><span style="font-size: 10pt; color: black;">”, </span><a href="http://en.wikipedia.org/wiki/Physical_Review" title="Physical Review" target="_blank"><i><span style="font-size: 10pt; color: black; text-decoration: none;">Physical Review</span></i></a><i><span style="font-size: 10pt;">, 61</span></i><span style="font-size: 10pt;">, 13, pp. 1446 – 1449.</span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__ednref4" name="131cbacf3c10ffba__edn4" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[4]</span></span></span></span></a> Another approach is to nip all these speculations in the bud, by pointing out, as Jeffrey Barrett does, that “One might argue that there can be no threat of temporal paradoxes in GTR (General Theory of Relativity) since a particular mass-energy distribution and spacetime either is or isnot a solution to the field equations--if it is, then the solution provides a model for all spacetime events” (personal communication).</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__ednref5" name="131cbacf3c10ffba__edn5" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[5]</span></span></span></span></a> <a href="http://en.wikipedia.org/wiki/David_Deutsch" title="David Deutsch" target="_blank"><span style="font-size: 11pt; color: black;">Deutsch, David</span></a><cite><span style="font-size: 11pt; color: black;"> </span></cite><cite><span style="font-size: 11pt;">(1991): "Quantum mechanics near closed timelike curves". </span></cite><cite><i><span style="font-size: 11pt;">Physical Review D</span></i></cite><cite><span style="font-size: 11pt;"> <b>44</b>: pp. 3197–3217.</span></cite></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__ednref6" name="131cbacf3c10ffba__edn6" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[6]</span></span></span></span></a> Thorne, K. (1994): pp. 508-516.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__ednref7" name="131cbacf3c10ffba__edn7" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[7]</span></span></span></span></a> Davies, P. (2003): <i>How to build a time machine</i>.<span> </span>Penguin Books, p. 96.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__ednref8" name="131cbacf3c10ffba__edn8" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[8]</span></span></span></span></a> <i>Ibid</i>., pp. 102-105. </p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__ednref9" name="131cbacf3c10ffba__edn9" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[9]</span></span></span></span></a> For some strange reason many physicists, including Thorne and Davies, thought at one time that the paradoxes of<span> </span>time travel arose out of the exercise of free will.<span> </span>Obviously that is not so.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__ednref10" name="131cbacf3c10ffba__edn10" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[10]</span></span></span></span></a> As quoted in Thorne (2003), p. 521. Vacuum fluctuations would destroy the wormhole before it can become a time machine.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__ednref11" name="131cbacf3c10ffba__edn11" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[11]</span></span></span></span></a> For a fascinating account see Brush, S.G. </p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__ednref12" name="131cbacf3c10ffba__edn12" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[12]</span></span></span></span></a> See, for example, “Bohr and evolutionary relativism,” Ch. 3 of my <i>Evolution and the Naked Truth</i>, Ashgate (1998).</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__ednref13" name="131cbacf3c10ffba__edn13" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[13]</span></span></span></span></a> Few ideas in the history of science have been corroborated as much as, say, Einstein’s formula for relativistic mass (discussed above).<span> </span>Practically every time we use a particle accelerator we confirm it with millions, perhaps billions of instances.</p> </div> <div> <p class="MsoNormal" style=""><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131cbacf3c10ffba__ednref14" name="131cbacf3c10ffba__edn14" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[14]</span></span></span></span></a> <span style="font-size: 10pt;">Another possibility – and this is admittedly speculation – would be a machine capable of producing the gravito-magnito effect described in Ch. 5.<span> </span>Ning Li predicted that a rapidly rotating disk (this experiment uses superconductors) would produce the kind of distortion of spacetime that the Gravity B Probe may measure for the planet Earth.<span> </span>Objects placed in front of such objects would show a decrease in mass!<span> </span>Experiments carried out by Podkletnov in 1992 apparently confirmed Li’s astonishing prediction.<span> </span>Unfortunately no one has been able to reproduce Podkletnov’s results.</span></p> <p> </p> </div> </div> </div></div>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-2186322634424624162011-08-07T14:54:00.000-07:002011-08-07T14:57:22.674-07:00To the Stars!<p class="MsoNormal"><b><span style="color: black;">Chapter 7E</span></b></p> <p class="MsoNormal"><b><span style="color: black;"> </span></b></p> <p class="MsoNormal"><b><span style="color: black;">To the Stars!</span></b></p> <p class="MsoNormal"><span style="color: black;"> </span></p> <p class="MsoNormal"><span style="color: black;"> </span></p> <p class="MsoNormal"><b><span style="color: black;">Note</span></b><span style="color: black;">: Although a little technical in a couple of places, I hope the reader will bear with me, for this is one of those cases where I need to bring up the technicalities for discussion.<span> </span>As I hope you will see, it is easier to see the point by doing a little bit of elementary algebra or chemistry.</span></p> <p class="MsoNormal"><u><span style="color: black;"><span style="text-decoration: none;"> </span></span></u></p> <p class="MsoNormal"><u><span style="color: black;">Human Expansion throughout the Galaxy</span></u><span style="color: black;"></span></p> <p class="MsoNormal" style=""><span style="color: black;"> </span></p> <p class="MsoNormal"><span style="color: black;">With present technology a trip to the nearest stars would take tens of thousands of years.<span> </span>Perhaps with an extension of our present capabilities we may be able to cut the journey to only a few centuries.<span> </span>Unless a truly fantastic technology for suspended animation is discovered, the trip would have to be completed by the descendants of the astronauts that begin it.<span> </span>Under those conditions the best way to travel to the stars might be to turn one of O'Neill's colonies into a vehicle and set it to depart from our solar system.<span> </span>But surely, some critics might say, people in their right minds would not wish to take their space colony into interstellar space for journeys that would last thousands of years -- although how preposterous the idea is will have to be determined by a level of technology and an abundance of resources in interstellar space that we are in no position to predict now.<span> </span>At any rate, even people in their right minds may consider precisely such a journey if they knew of some unavoidable catastrophe that was to befall the solar system, or for other reasons that we may not fathom at this time. </span></p> <p class="MsoNormal"><span style="color: black;"><span> </span>Nevertheless, in journeys so long that only the descendants of the original travelers can complete them, a successful outcome may seem remote at best. Accordingly, some feel that the next great barrier to space exploration is the development of technology that would permit interstellar travel during a human lifetime.<span> </span>Since the closest stars are at least four light years away, and our galaxy is about one hundred thousand light years across, we would need starships that achieve velocities close to that of light. </span></p> <p class="MsoNormal"><span style="color: black;"><span> </span>Many scientists, however, believe that Einstein's special theory of relativity does not permit to accelerate spaceships close to that of light. And accelerating spaceships beyond the speed of light is simply forbidden by that theory. Nevertheless as we will see below, Einstein's physics does not in principle preclude either of these options. </span></p> <p class="MsoNormal"><span style="color: black;"><span> </span>Let us consider the first option.<span> </span>Although Alpha Centauri is only four light years away, the majority of stars of interest in the galaxy are tens, hundreds, or thousands of light years away.<span> </span>It may seem then that even if we could achieve relativistic velocities, traveling to the stars may take as long as the astronauts’ life spans, or longer.<span> </span>Fortunately, distance and time are relative to the inertial frame of reference in which they are measured (in an inertial frame of reference the velocity is uniform).<span> </span>In a ship that travels at great velocity with respect to us, time slows down and distances shorten, even though the astronauts themselves detect no abnormality.<span> </span>At velocities close to that of light, 300,000 Km/s, distances are so short (or alternatively, the dilation of time is so large that apparently unbelievably long journey became feasible.<span> </span>According to calculations by Carl Sagan, we could go to many interesting stars and come back in a decade or two, ship time<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn1" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref1" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[1]</span></span></span></span></a>.<span> </span>Six years of ship time would go by in a round trip to Alpha Centaury (eight years Earth time), 22 to the Pleiades (800 years Earth time), and to the Galaxy of Andromeda, which is over a million light years away, the round trip would only take about five decades!</span></p> <p class="MsoNormal"><span style="color: black;"><span> </span>In the meantime nearly three million years would have gone by on the Earth, and so the return may offer more of a shock than what we might find in Andromeda.<span> </span>Most of us would not want to go on such a journey, but I imagine that the project would suffer no dearth of volunteers.<span> </span>The main problem, however, would be the energy required.<span> </span>At a constant acceleration of 1 g our spaceship would reach 99% of the speed of light in one year.<span> </span>But in reaching a velocity that high we would need to spend, according to some calculations, energy equal to the entire consumption in United States during a period of a million years!<span> </span>Enthusiasts like to point out that the first spaceship that went to the Moon spent an amount of energy tens of thousands of times larger than what many societies used only a century earlier. <span> </span>Bernard Oliver, who frowned on the idea of interstellar travel, thought that the requirements would be of this order of magnitude<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn2" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref2" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[2]</span></span></span></span></a>.<span> </span><span> </span>Even if such calculations are off by an order of magnitude or two, we are talking about staggering amounts of energy.</span></p> <p class="MsoNormal"><span style="color: black;"><span> </span>Some skeptical theorists have thought that the project is impossible, anyway, because as the velocity increases, so does the mass (also according to the special theory of relativity).<span> </span>But a larger mass requires larger energies to increase the velocity, which then increases the mass, and so on.<span> </span>This continuous increase in the mass of the spaceship eventually defeats the attempt to increase its velocity: we never reach a velocity close to that of light. </span></p> <p class="MsoNormal"><span style="color: black;"><span> </span>I do not believe that this objection works, however, for it does not take into account that from the point of view of the ship itself the mass has not increased.<span> </span>On the contrary, as most ships are conceived, it necessarily decreases as the engine burns fuel.</span></p> <p class="MsoNormal" style=""><span style="color: black;"><span> </span>The skeptics’ suggestion is, again, that as the traveler approaches the speed of light, the mass increases so that it takes more and more energy to keep accelerating at the same rate.<span> </span>Many physicists, using this line of reasoning, conclude that it is impossible to travel at the speed of light, let alone faster.<span> </span>At least it seems that such is the reasoning that leads physicists like Smolin to conclude that, “…her mass increases as she approaches the speed of light.<span> </span>Were her speed to match that of light, her mass would become infinite.<span> </span>But one cannot accelerate an object that has infinite mass, hence one cannot accelerate an object to the speed of light and beyond.”<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn3" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref3" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[3]</span></span></span></span></a> Similar remarks are made by Brian Greene<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn4" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref4" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[4]</span></span></span></span></a> and even by Stephen Hawking<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn5" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref5" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[5]</span></span></span></span></a>.</span></p> <p class="MsoNormal" style=""><span style="color: black;"><span> </span>I think this line of reasoning is misleading in two ways.<span> </span>First, once again, as far as the special theory of relativity is concerned, the mass and the corresponding energy requirements increase only from the point of view of the observers left behind on Earth.<span> </span>But from the point of view of the star travelers, who are at rest with respect to the ship, the mass of the ship does not increase at all, and therefore accelerating the ship is not particularly more daunting than it was at lower velocities. If anything, it is easier because the longer the ship accelerates the more fuel it uses, and therefore the more mass it loses, as I pointed out above.<span> </span>At speeds close to that of light, its rest mass should be considerably less than at the beginning of its journey, as long as you have the standard means of propulsion, i.e., shooting something out the back.<span> </span>In practice, or course, the faster a starship travels, the greater the resistance from the interstellar medium, which could become significant depending on the ship’s design and other factors.<span> </span>But this is a different type of concern altogether.</span></p> <p class="MsoNormal"><span style="color: black;"><span> </span>Second, the reason why the ship cannot match the speed of light has nothing to do with the mass becoming infinite.<span> </span>What physicists like Smolin, Greene, and Hawking have in mind is Einstein’s equation:</span></p><p class="MsoNormal"><br /><span style="color: black;"></span></p><p class="MsoNormal" style=""> </p><p class="MsoNormal" style=""><span style="color: black;">m=<i> </i><span>m<sub>0</sub>/(1- v<sup>2</sup>/c<sup>2</sup> )<sup>1/2</sup></span></span></p><div><div class="im"> <p class="MsoNormal"> </p><p class="MsoNormal" style=""><span style="color: black;"> </span></p> <p class="MsoNormal"><span style="color: black;">where <i>m</i> is the mass of th</span>e ship from the point of view of the observer, <i>m<sub>0</sub> </i>is the rest mass, <i>v</i> is the velocity of the ship with respect to the observer, and <i>c</i> is the speed of light. </p><span style="color: black;"><span></span></span> <p class="MsoNormal" style=""><span style="color: black;"><span> </span>As <i>v</i> gets closer to <i>c</i>, the term <i>v<sup>2</sup>/c<sup>2 </sup></i>approaches 1.<span> </span>This means that the denominator approaches 0, which makes <i>m </i>approach infinity.<span> </span></span></p> <p class="MsoNormal" style=""><span style="color: black;"><span> </span>But <i>m</i> can never reach infinity for the simple reason that, if the velocity of the ship reached that of light, the denominator would become 0 and the function would be undefined.<span> </span>The problem is not that an infinite mass is physically inconceivable, but that the mathematical expression makes no sense.</span></p> <p class="MsoNormal" style=""><span style="color: black;"><span> </span>The main insight is flawed, in any event. Infinite mass has nothing to do with the relativistic speed limit.<span> </span>The reason why a ship cannot accelerate to the speed of light is that Einstein’s formula for addition of velocities (based in part on the postulate that the speed of light is a constant) will always yield final velocities less than <i>c</i>. </span></p> <p class="MsoNormal" style=""><span style="color: black;"><span> </span>If I am traveling in a ship at .5 <i>c</i>, the speed of a ray of light with respect to me, whether it goes towards me or away from me, still is 300,000 km/sec.<span> </span>If I fire a probe that travels at .5 <i>c</i> with respect to me, the speed of that ray of light would still be 300,000 km/sec with respect to the probe. </span></p> <p class="MsoNormal" style=""><span style="color: black;"><span> </span>The result is that, according to Einstein<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn6" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref6" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[6]</span></span></span></span></a>, in the special theory of relativity I cannot just add the velocities of my ship with respect to the ground (<i>v<sub>s</sub></i>) and of the probe with respect to me (<i>v<sub>p</sub></i>).<span> </span></span></p> <p class="MsoNormal" style=""><span style="color: black;"><span> </span>That addition must be divided by the term 1+ <i>v<sub>s</sub></i>.<i>v<sub>p</sub></i>/<i>c<sup>2</sup></i>.<span> </span>When I add the velocities (my ship’s plus the probe’s) I do not get c, therefore, but only .8 <i>c</i>.</span></p> <p class="MsoNormal" style=""><span style="color: black;"><span> </span>This corrected interpretation of the situation (from the point of view of the astronaut, and the appropriate equations from the special theory of relativity) still seems to forbid travel at or faster than the speed of light.<span> </span>It leaves open the question of building a spaceship that comes very close to the speed of light, though.</span></p> <p class="MsoNormal"><span style="color: black;"><span> </span>There have been other attempts to prove that near-light speed travel is impossible, and there have been many refutations of such attempts as well.<span> </span>Of the presently available starship technologies (available in theory, that is) some form of controlled fusion may offer the best hope to achieve relativistic speeds (though just barely about 1/10 of the velocity of light).<span> </span>The ideal apparently would be a matter- antimatter engine, for it would convert all of the fuel's mass into energy as the particles and antiparticles annihilate each other.<span> </span>A serious problem is how to produce the necessary amounts of antimatter without spending more energy than that required to propel the starship.<span> </span>And if you do produce it, you then have to worry about how to channel it so it goes out the nozzle only, otherwise it will radiate in all directions. And there is also the already familiar difficulty that if you include all the fuel you need to keep accelerating the starship, then you need to build a much larger starship, which then needs even more fuel, and thereby an even larger starship.</span></p> <p class="MsoNormal"><span> </span>To get around these problems we might employ starships that do not carry their fuel on board but take it from their environment.<span> </span>The first such "design" was for an interstellar fusion ram-jet that would scoop hydrogen ions from space, the Bussard Ramjet<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn7" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref7" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[7]</span></span></span></span></a>.<span> </span>Bussard’s interesting idea was marred by several difficulties, especially that it would require a scoop 160 Km in diameter and that it would use a proton-proton fusion reaction that may work only in temperatures as hot as the interior of stars<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn8" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref8" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[8]</span></span></span></span></a>.<span> </span>A modified version, the Whitmire catalytic nuclear ramjet,<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn9" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref9" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[9]</span></span></span></span></a> apparently solves some of the main theoretical problems (it works by scooping up the hydrogen ions and running them through a catalytic nuclear reaction cycle, i.e., a nuclear reaction that repeats itself again and again, and that returns to the starting point of the reaction extremely fast so a new batch of protons can be used to propel the starship).</p> <p class="MsoNormal"><span> </span>One possible sequence or reactions would be, for example, that of the catalytic cycle of carbon-nitrogen-oxygen (CNO), which occurs in the thermonuclear reactions of very hot starts:</p> <p class="MsoNormal"> </p> <p class="MsoNormal" style="margin-left: 0.5in;"><sup><span lang="ES-CO">12</span></sup><span lang="ES-CO">C + <sup>1</sup>H</span><span style="font-family: Wingdings;"><span>à</span></span><sup><span lang="ES-CO">13</span></sup><span lang="ES-CO">N + </span>γ<span lang="ES-CO"></span></p> <p class="MsoNormal" style="margin-left: 0.5in;"><sup><span lang="ES-CO">13</span></sup><span lang="ES-CO">N + <sup>1</sup>H</span><span style="font-family: Wingdings;"><span>à</span></span><sup><span lang="ES-CO">14</span></sup><span lang="ES-CO">O + γ</span></p> <p class="MsoNormal" style="margin-left: 0.5in;"><span lang="ES-CO"><span> </span><sup>14</sup>O</span><span style="font-family: Wingdings;"><span>à</span></span><sup><span lang="ES-CO">14</span></sup><span lang="ES-CO">N + e<sup>+ </sup>+ ν</span></p> <p class="MsoNormal" style="margin-left: 0.5in;"><sup><span lang="ES-CO">14</span></sup><span lang="ES-CO">N + <sup>1</sup>H</span><span style="font-family: Wingdings;"><span>à</span></span><sup><span lang="ES-CO">15</span></sup><span lang="ES-CO">O + γ</span></p> <p class="MsoNormal" style="margin-left: 0.5in;"><span lang="ES-CO"><span> </span><sup>15</sup>O</span><span style="font-family: Wingdings;"><span>à</span></span><span lang="ES-CO">15N + e<sup>+</sup> + </span>ν<span lang="ES-CO"></span></p> <p class="MsoNormal" style="margin-left: 0.5in;"><sup><span lang="ES-CO">15</span></sup><span lang="ES-CO">N + <sup>1</sup>H</span><span style="font-family: Wingdings;"><span>à</span></span><sup><span lang="ES-CO">12</span></sup><span lang="ES-CO">C + <sup>4</sup>He</span></p> <p class="MsoNormal"><span lang="ES-CO"> </span></p> <p class="MsoNormal">As we can see, the hydrogen ions (protons) react with the carbon isotope (<sup>12</sup>C) to begin the cycle, which, after utilizing a total of four protons, ends again in <sup>12</sup>C plus a helium nucleus that is expelled out the nozzle, thus propelling the ship forward.<span> </span>The positrons (e<sup>+</sup>) react with the electrons that remain from the ionization process and liberate additional energy in the form of gamma rays<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn10" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref10" title=""><span><span lang="ES-CO"><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";" lang="ES-CO">[10]</span></span></span></span></span></a>. <span> </span></p> <p class="MsoNormal"><span> </span>Whitmire and others<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn11" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref11" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[11]</span></span></span></span></a> have worked on the possibility of either electromagnetic or electrostatic scoops of dimensions in the hundreds of meters, rather than kilometers, to reduce the immense proton and electron drag expected to affect a ship moving at relativistic speed (and that would be more efficient in the collection of protons).<span> </span>There are several practical problems with Whitmire’s design, the most nagging of which is that the temperatures in his reactor might reach temperatures of <i>one billion degrees Kelvin!</i></p> <p class="MsoNormal"><span>There are also problems raised by the gravitational impact of a ship that moves through a medium with respect to which its mass increases extraordinarily (even if it does not change for the astronauts).<span> </span>It is possible that the ship may affect the structure of spacetime in its path.<span> </span>There would be additional problems to describe mathematically the interactions between the ship and the environment, using the general theory of relativity, for the ship will exchange energy with the particles closest to it as it accelerates, which would then cause all sorts of difficulties for the calculation of the relevant masses.</span></p> <p class="MsoNormal"><span> </span>Whether these problems can be solved eventually, I do not know.<span> </span>Nevertheless the interesting result is that, in principle, interstellar hydrogen can be used to accelerate a starship at 1g to achieve speeds arbitrarily close to that of light.</p> <p class="MsoNormal"> </p> <div><br /> <hr size="1" width="33%" align="left"> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref1" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn1" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[1]</span></span></span></span></a> C. Sagan, “Direct Contact Among Galactic Civilizations by Relativistic Spaceflight,” <i>Planetary and Space Science</i> 11 (1963): 485-498.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref2" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn2" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[2]</span></span></span></span></a> B.M. Oliver, “Efficient Interstellar Rocketry,” Paper IAA-87-606, presented at 38<sup>th</sup> I. A. F. Congress, Brighton, UK., 10-17 October 1987.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref3" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn3" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[3]</span></span></span></span></a> Smolin…</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref4" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn4" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[4]</span></span></span></span></a> Brian Greene, <i>The Elegant Universe</i>, Vintage Books (2003): 52.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref5" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn5" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[5]</span></span></span></span></a> Stephen Hawking, <i>The Universe in a Nutshell</i>, Bantam Books (2001):12.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref6" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn6" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[6]</span></span></span></span></a> Albert Einstein, “On the Electrodynamics of Moving Bodies,” reprinted in <i>The Principle of Relativity</i>, with H.A. Lorenz, H. Minkowski and H. Weyl, Dover Publications, 1952 (republication of translation published by Methuen and Company, 1923).<span> </span>His equation as it appears in Section 5 of the article (“Composition of Velocities”), when the direction of motion of v and w is along the X axis, is:</p> <p style="text-indent: 0.5in;">V= v + w/1+ vw/c<sup>2</sup></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref7" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn7" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[7]</span></span></span></span></a> R.W. Bussard, “Galactic Matter and Interstellar Spaceflight,” <i>Astronautica Acta </i>6 (1960): 179-194.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref8" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn8" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[8]</span></span></span></span></a> For an interesting discussion of this and other possible starships, please see E. Mallowe and G. Matloff, <i>The Starflight Handbook: A Pioneer’s Guide to Interstellar Travel,</i> John Wiley and Sons, Inc (1989): 89-149.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref9" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn9" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[9]</span></span></span></span></a> D. P. Whitmire, “Relativistic Spaceflight and the Catalytic Nuclear Ramjet,” <i>Acta Astronautica</i> 2 (1975): 497-509. </p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref10" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn10" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[10]</span></span></span></span></a><span lang="ES-CO"> Otros ciclos catalíticos como el del <sup>20</sup>Ne también serían posibles.<span> </span>El tope de la energía generada por el reactor de Whitmire sería unos 10<sup>11</sup> megawatts, cerca de 10.000 veces lo producido por el mundo entero hoy en día (Mallowe y Matloff, p. 114).</span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__ednref11" name="131a63bb60179ebb_131a61f9566213ae_131a6155ca5251e7__edn11" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[11]</span></span></span></span></a> See again Mallove and Matloff, <i>op. cit.</i>, 124-133.</p> </div> </div> </div></div>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com3tag:blogger.com,1999:blog-5232161716029893381.post-24228677426780672011-07-28T17:07:00.000-07:002011-07-28T17:09:09.728-07:00At Home in the Solar System<p class="MsoNormal"><b><span style="color: black;">CHAPTER 7D</span></b></p> <p class="MsoNormal"><b><span style="color: black;"> </span></b></p> <p class="MsoNormal"><b><span style="color: black;">SPACE EXPLORATION IN THE LONG RUN</span></b></p> <p class="MsoNormal"><span style="color: black;"> </span></p> <p class="MsoNormal"><span style="color: black;">How far can the human horizon in space expand?<span> </span>Space enthusiasts should not assume that this is merely an incremental matter. Let me consider first the possibility of colonizing the solar system, and then of expanding into the galaxy.</span></p> <p class="MsoNormal"><span style="color: black;"> </span></p> <h1>At Home in the Solar System</h1> <p class="MsoNormal"><span style="color: black;"><span> </span></span></p> <p class="MsoNormal"><span style="color: black;">Colonizing the solar system requires that we solve the serious problem of prolonged exposure to radiation.<span> </span>Better shields, faster spaceships, and piles of dirt on top of our outposts should help a great deal.<span> </span>Better shields are within our technological means, and piling dirt on top of, say, inflatable dwellings should not present any major obstacles.<span> </span>Faster spaceships have been on the drawing board for a long time: fission rockets, fusion rockets, ion propulsion rockets, laser-propelled rockets, and even solar sails.<span> </span>Fission rockets and ion propulsion rockets would use tried-and-true technologies.<span> </span>Ion propulsion, for example, works on the principle of particle accelerators: you take a charged particle and you accelerate it by means of electromagnetic coils; the particle picks up a very large exhaust velocity and, by Newton’s Third Law, it propels the rocket forward.<span> </span>The solar sail would use the solar wind to move around the inner solar system with great ease and at great speeds.<span> </span>It would consist of very large sails made of very thin sheets of metal that would move under the pressure of the solar wind.<span> </span>The Planetary Society, an organization of space enthusiasts, has arranged with the Russian space program for a deployment in space of such a device in the near future.<span> </span>All these three systems could in principle reduce a trip to Mars from about a year, on the average, to perhaps as little as three months or less.</span></p> <p class="MsoNormal"><span style="color: black;"><span> </span>We also need to solve the physiological problems created by microgravity.<span> </span>Perhaps the best solution is simply to create what is sometimes called "artificial gravity", which is not more than an application of the equivalence between acceleration and gravitational attraction.<span> </span>If a ship accelerates at a rate of approximately 10m/sec2, which is the value of 1 g, a passenger would feel as if he were on the surface of the Earth (a favorite illustration is of an elevator that ascends to the heavens unbeknownst to an unsuspecting passenger; as the elevator accelerates, its floor comes up to push against the passenger's feet, which to him feels as if he were being drawn towards the floor). </span></p> <p class="MsoNormal"><span style="color: black;"><span> </span>Another way to achieve the same result is to construct very large ships or habitats that rotate.<span> </span>At the appropriate rate of rotation someone on the ground floor -- next to the outer shell -- would experience a centrifugal acceleration equivalent to the Earth's gravity.<span> </span>The reason this technique is not used on present spaceships is that, since they are relatively small, they would have to rotate extremely fast, which would subject the astronauts to coriolis forces (if you are an astronaut, your head would feel a certain acceleration and your stomach another).<span> </span>Those effects, in addition to the extremely fast rotation may play havoc with the control of the ship. Large structures on the scale of Gerard O'Neill's space colonies would not have such problems, but using a space colony as a spaceship would require seemingly prohibitive amounts of energy, at least in the near future.<span> </span>The most reasonable alternative would be to connect the spaceship to a cargo module by a very long tether, and to have the two rotate around their common center of gravity.<span> </span>If the distance between the space ship and the axis of rotation is 200 meters, for example, we would have the equivalent acceleration that a gigantic spaceship or a small space colony might enjoy.</span></p> <p class="MsoNormal"><span style="color: black;"><span> </span>The first colonies on the Moon, on Mars, and on the moons of the outer planets would be dedicated mainly to the scientific exploration of those worlds, but also to determining the feasibility of even bigger settlements. As our presence grows so will the opportunities for space science (although I am sure there will be drawbacks on occasion), but I presume that another transformation of great consequence will take place: if the solar system becomes our home, then all the arguments about the serendipity of space exploration will gain additional force.<span> </span>Surely the change in our views will not be about alien worlds far away --it will affect our understanding of our new habitat.<span> </span>Once we are up there in force, the panorama of scientific, technological, industrial, and social opportunities may seem vastly different from what we may imagine today.</span></p> <p class="MsoNormal"><span style="color: black;"><span> </span>As those colonies grow, they will transform their extraterrestrial environments. The point may come when we engage in the science, or art, of "terraforming," which at its most grandiose envisions transforming entire planets and giant moons into habitable worlds. If a world does not have enough water, for example, we bring to it one of the thousands of small asteroids from the Kuiper belt composed mainly of water.<span> </span>Crashing the asteroid into that world would also help to increase the density and raise the temperature of the atmosphere.<span> </span>In another world, Venus for instance, that receives too much sunlight, we could place a cloud of dust around it, and then manipulate its atmosphere to reduce its greenhouse effect considerably.</span></p> <p class="MsoNormal"><span style="color: black;"><span> </span>Decades, probably centuries, will pass before we understand planet dynamics well enough to attempt to transform any world into a second Earth.<span> </span>In any event, we need remember that the initial justification for setting up human habitats in places like Mars is the possibility for the profound transformation of our planetary science.<span> </span>In the case of Mars, the most compelling reason is the possibility of transforming our understanding of human life by comparing it with Martian life, or at least with the fossils of Martian life.<span> </span>But all the other “Earth” sciences are likely to profit as well – geophysics, climatology, etc.<span> </span>Thus it would be highly irresponsible to begin to terraform Mars before we learn from it what it has to teach us.<span> </span>Indeed, we will need to learn many lessons from Mars, and Venus, and Titan, before we can begin to feel confident that our terraforming theories will be worth undertaking on them or on any other world.</span></p> <p class="MsoNormal"><span style="color: black;"><span> </span>Speculations of this sort are not only entertaining, they bring up the possibility that the limits to human expansion into the cosmos may be very far from our home planet, perhaps very far from the solar system. To that possibility I now turn.</span></p>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-30592782100319159322011-07-16T14:18:00.000-07:002011-07-16T14:19:39.494-07:00The Value of Human Exploration<div id=":8t" class="ii gt"><div id=":8u"> <p class="MsoNormal"><b><span style="font-size: 12pt; color: black;">Chapter 7C</span></b></p> <p class="MsoNormal"><b><span style="font-size: 12pt; color: black;">The Value of Human Exploration</span></b></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;">Still, the proponents of manned exploration have a point – or rather, several.<span> </span>First, they might just as well acknowledge that the Shuttle has set space science back many years. Even the head of NASA thinks it was a mistake.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__edn1" name="13134c80e5813d9c__ednref1" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[1]</span></span></span></span></a> But they might point out that the Shuttle is a very poorly designed system, not a good example of how manned exploration should be done.<span> </span>It is essentially a very large and heavy glider taken into low orbit by a partially reusable combination of solid and liquid fuel propulsion engines.<span> </span>It is at its worst when it ferries satellites into orbit, a task to which it was devoted through the 1980s, and for which it is still used.<span> </span>Suppose that I am eating dinner in Tokyo next to a sumo wrestler.<span> </span>Across the dining room a friend asks me for the small pitcher of warm saki.<span> </span>I could get up and take it to him.<span> </span>It would require me to spend a certain amount of energy, but not much, and to incur a certain amount of risk, but not much.<span> </span>Or I could hand the pitcher to the sumo wrestler and then carry him, saki in hand, across the room so he can give the saki to my friend.<span> </span>The energy required is far greater, as is the risk involved, both to the sumo wrestler and to me.<span> </span>Indeed, that is an extremely expensive and unsafe way to ferry satellites into orbit (or carry saki across a dining room).<span> </span>To make matters worse, the Shuttle is an extremely complicated machine, with more ways to fail than anything else that has flown before or since.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>Was there a better way to fly people into space?<span> </span>Of course there was.<span> </span>Otherwise we would have never landed a man on the Moon and returned him safely to Earth “before the decade was out” as President Kennedy challenged us to do in the early 1960s.<span> </span>And when we went to the Moon, let us recall, there were also many complaints about the poor quality of the science that was expected to result.<span> </span>Those complaints were very misguided.<span> </span>The Apollo astronauts made great contributions to science, contributions, for example, to our understanding of the origin and evolution of our planet.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__edn2" name="13134c80e5813d9c__ednref2" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[2]</span></span></span></span></a></span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>That Apollo era saw the flowering of unmanned exploration as well, a flowering that continued through the mid-1970s, until NASA put its rockets in mothballs and forced practically the entire U.S. space program into the coming “space bus” – the Shuttle.<span> </span>That era also gave us a reliable and relatively inexpensive space station, Skylab, which burnt in reentry when its orbit decayed and NASA no longer had rockets to move it into a higher orbit.<span> </span>The Russians, with a somewhat more modest program also based on rockets, had a very active exploration of the solar system and a station of their own: Mir.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>So the important question is whether we should explore with people and with machines, as long as we have a sensible means again for ferrying astronauts into space.<span> </span>We could, for example, jettison the shuttle and continue using the Russian rockets until we have a good rocket program of our own again.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__edn3" name="13134c80e5813d9c__ednref3" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[3]</span></span></span></span></a><span> </span>We could also encourage private undertakings such as Spaceship1, which promise far cheaper access into space for astronauts.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__edn4" name="13134c80e5813d9c__ednref4" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[4]</span></span></span></span></a><span> </span></span><span style="font-size: 12pt; color: red;"></span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>In the meantime, though, we should realize that manned exploration is once again poised to help advance the cause of space science.<span> </span>I am referring to the search for life, or for fossils of life, in Mars.<span> </span>Rovers and other machines are already exploring the planet, finding evidence of water, laying the groundwork for when human geologists and paleontologist finally arrive, for practically all agree that their presence will be needed in this extraordinarily significant endeavor.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;">THE VALUE OF A PERMANENT HUMAN PRESENCE IN SPACE</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;">The critics' fear is that the space station once again signals the commitment of the country to expensive manned exploration, with glamour winning over substance.<span> </span>I have already argued that there is more than glamour to the presence of humans in space.<span> </span>It is now time to take this argument further. Unless we had money to burn, it is difficult to justify a transcontinental journey to Paris for the sole purpose of sitting at a cafe to watch people go by as we sip a brandy or a cup of <i>cafe au lait</i>.<span> </span>But if we had to go to Paris for some other reason, it would make perfectly good sense to enjoy that aspect of Parisian life as well. Similarly a permanent manned presence in space – even if prompted by reasons of commerce or national prestige – would make feasible a multiplicity of scientific experiments that a society might not be willing to undertake otherwise. My suspicion is, then, that a permanent human presence in space would, if anything, help a new flowering of space science.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>I am not here talking about the occasional grandiose project that becomes an end in itself and leaves more memories than it does future avenues of investigation.<span> </span>I am talking about a space station that marks the beginning of the sustained expansion of the human species into the solar system.<span> </span>Since that is the fear, that is the situation I would like to discuss.<span> </span>How can space science be well served by such an expansion during a period of fifty to a hundred years from today? </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>Since some branches of space science are obviously helped by a human presence, or so I hope to have shown, the issue is how space science as a whole is to be helped.<span> </span>We must consider, then, what effects that human presence will have on space astronomy, planetary exploration, and other areas where the human experimenter is either not wanted or has been traditionally absent.<span> </span>In space astronomy there is a clear initial benefit: the repair and regular maintenance of the large telescopic arrays in orbit. The role of servicing the Hubble visual telescope, for example, requires the ability of astronauts to fly to the telescope and work on it.<span> </span>(While the shuttle was out of commission, space scientists tried to design a robotic mission, but its future is uncertain; if it fails, the Hubble telescope will have its useful life cut short because astronauts could no longer reach it.)<span> </span>A space station would enhance significantly the capacity to support in space astronomical observatories of even larger magnitude (once we build spacecraft that station occupants can use for travel in orbit).<span> </span>This goal can be achieved in the next two or three decades, definitely a period in which humans are not likely to be replaced by their mechanical contraptions. </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>This role gives but a mere inkling of what humans in space can do for astronomy. As the expansion into space continues, it becomes possible to build even larger observatories that would be too difficult to take up in one piece.<span> </span>And it also becomes possible to place those observatories in many locations away from the Earth, either because of convenience – e.g., on the other side of the Moon, so as to shield them from the electromagnetic interference from the Earth – or simply to increase the baseline of the measurements.<span> </span>And these possibilities point to some aspects of a permanent human presence of potentially far greater significance. </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>Apart from producing goods that can be used on Earth, space labs and factories can build technology for space itself. There are several ways in which large space structures might be very advantageous, and some of them will merit discussion shortly.<span> </span>But my point goes further. A lot of the technology used in unmanned space flight today has to be built with the problems of lift-off, orbiting, and deployment in mind. It has to meet terrestrial conditions, withstand the accelerations and temperatures involved in the transportation from ground to orbit, its final stage must be fitted to the specifications of the boosters, and then it has to manage in space. But is all this necessary? </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>Having a technology that can meet all these challenges is no doubt beneficial.<span> </span>But imposing them on all technology and all experiments that go into space is not very reasonable unless there are no alternatives.<span> </span>It is not reasonable because it imposes greater difficulties and cost in design and production.<span> </span>Take the gravitational gyroscopes designed to test some extraordinary predictions of Einstein’s General Theory of Relativity (the Gravity Probe B experiment<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__edn5" name="13134c80e5813d9c__ednref5" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[5]</span></span></span></span></a>).<span> </span>To have the spheres suspended you must use thousands of volts on the Earth, and you must design and build the sphere so it can withstand that electrical potential, even though in space the amount of electricity used will be very small.<span> </span>If we could do the experimental development in space, many of these specification problems would be automatically solved. Not that it would pay now to send scientists to do that development in orbit.<span> </span>The point is rather that a massive, permanent human presence in space opens up a lot of possibilities for space science because it would be relatively feasible to undertake them under those conditions.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>In this regard planetary exploration can be a clear beneficiary, since the requirements for an interplanetary probe to be launched from space may be far more relaxed. For example, rather flimsy structures may be perfectly adequate in propulsion modules. We could also employ vacuum tubes without going to the trouble of producing a vacuum artificially – indeed without a "tube" at all, just a cathode, anode, grids, and relevant circuitry.<span> </span>And of course the superior semi-conductors and crystals that can be produced in microgravity would be deployed in space technology without some of the costs of transportation up and down the gravity well of the Earth.<span> </span>The point is that once we make ourselves at home in space many possibilities for technological innovation in space will become readily apparent.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>This point is made stronger when we realize that it is possible to avail ourselves of the resources of space in the development of such technologies, as well as in the development of products for the Earth.<span> </span>Once in place, a vigorous exploitation of the minerals and energy of the solar system can make important contributions to an infrastructure that may support the routine exploration of the planets.<span> </span>This is not to say that we should commit ourselves to such exploitation at this time.<span> </span>Indeed one of the present tasks of solar system exploration is to determine the availability and distribution of such resources. Nor can we expect to have the complete means for taking advantage of those resources immediately, even if we wanted to.<span> </span>But as our presence in space becomes wider and better established it is reasonable to expect that we will begin to use the native materials.<span> </span>Plans are already being prepared for that eventuality, and so the promise of space may be more fully realized once we make it our environment.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>The ability to create very large structures in space, which for at least many decades is likely to require astronauts, will make possible to assemble very large solar sails and other forms of propulsion that will considerably shorten the travel times and increase the distances our spacecraft can travel. That is also going to have a beneficial effect on all of space science. </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>The urge to explore the solar system must of necessity go hand in hand with scientific exploration.<span> </span>A survey of what Mars has to offer to potential colonists, for example, would require first an extensive scientific survey of Mars.<span> </span>And any plans for setting up such a colony, as well as for the extraction and processing of materials would at the very least challenge our talents in several branches of space science.<span> </span>Eventually advanced science would no longer be necessary for the technology of prospecting and colonization, since a very well tried science will become routine.<span> </span>This is not to suggest that science is always a prerequisite for technology.<span> </span>The industrial revolution was spurred as much by the development of craft as by the great intellectual feats of science.<span> </span>The relationship between science and technology is clearly dialectical – changes in science affect areas of technology, which in turn make scientific change possible, and so on – although just as clearly at any one time there is also a good deal of independence between them.<span> </span>In this case, however, the nature of the exploring to be done has a major scientific component, in that the questions that we need to ask are not different from the kinds of questions that many planetary scientists would like to ask. Thus the technology to be developed would not only depend on the scientific answers to these questions but would also to a large extent be guided by them.<span> </span>Even at the level of building a colony, we need to progress trough a series of experiments on ecological loops if we have any hope of designing human outposts that approach self-sufficiency.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>A significant human presence throughout the solar system would not only enhance by orders of magnitude the amount and quality of space science, but also would change drastically the very conception of what may be done in and with space science.<span> </span>Once we are in space permanently the range of possibilities is also altered permanently, not only because humans are around to lend a helping hand, but because they are there under conditions that permit them to move with far greater ease. There are simply far more starting points for space science research, a radically different interplay with a different technology, and a qualitative difference in what may be undertaken.<span> </span>In areas where success turns exploration into routine colonization, the frontiers of science will move further outward, and those that remain may not be so closely connected anymore with the day-to- day activities of the ordinary humans in space. But that turning of the extraordinary into the commonplace will not happen overnight.<span> </span>And when it does, it may simply point to a new horizon of opportunity for science and technology beyond what has just been reached.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>The first colonies on the Moon, on Mars, and on the moons of the outer planets would be dedicated mainly to the scientific exploration of those worlds, but also to determining the feasibility of even bigger settlements. As our presence increases so will the opportunities for space science (although I am sure there will be drawbacks on occasion.<span> </span>Once we are up there in force, the panorama of scientific, technological, industrial, and social opportunities may seem vastly different from what we may imagine today.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>As those colonies grow, they will transform their extraterrestrial environments. The point may come when we engage in the science, or art, of "terraforming," which at its most grandiose envisions transforming entire planets and giant moons into habitable worlds<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__edn6" name="13134c80e5813d9c__ednref6" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[6]</span></span></span></span></a>. If a world does not have enough water, for example, we bring to it one of the thousands of small asteroids from the Kuiper belt composed mainly of water.<span> </span>Crashing the asteroid into that world would also help to increase the density and raise the temperature of the atmosphere.<span> </span>In another world, Venus for instance, we could place a cloud of dust around it to reduce the amount of light it receives from the sun, and then manipulate its atmosphere to reduce its greenhouse effect considerably.<span> </span>We might thus achieve a range of temperatures amenable to life.</span></p> <p class="MsoNormal" style=""><span style="font-size: 12pt; color: black;"><span> </span>Decades, probably centuries, will pass before we understand planet dynamics well enough to attempt to transform any world into a second Earth, a task that should not begin until we have learned the scientific lessons those worlds have to teach us.<span> </span>But eventually, it may open up new niches to our species. </span><span style="font-size: 12pt;">In the truly long run, but long before the sun becomes a red giant, the Earth’s “thermostat” is likely to malfunction.<span> </span>James Lovelock, of Gaia fame, and M. Whitfield argued in a 1982 article that life was steadily removing CO<sub>2</sub> from the atmosphere – it actually has been doing so for the last 400 million years, since plants conquered the land – and in about 100 million years the level of CO<sub>2</sub> will go below 150 parts per million (ppm) of air.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__edn7" name="13134c80e5813d9c__ednref7" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[7]</span></span></span></span></a><span> </span>This level is important because most plants require at least as much atmospheric CO<sub>2 </sub>to survive. Newer forms of plants – grass, palm trees – use slightly different mechanisms for photosynthesis and can go well below the 150 ppm.<span> </span>The flora of the future, then, will have a very different view: gone will be the apple orchards and the rose gardens, replaced by new and exotic varieties of plants.<span> </span>Inexorably, unless we intervene, the level of atmospheric CO<sub>2</sub> will go below 10 ppm and photosynthesis will come to an end altogether.<span> </span>More recent studies following on Lovelock and Whitfield’s footsteps have revised their estimate to between 500 million and a billion years.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__edn8" name="13134c80e5813d9c__ednref8" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[8]</span></span></span></span></a></span></p> <p class="MsoNormal" style=""><span style="font-size: 12pt;"><span> </span>The loss of plants will be a catastrophe for animals, obviously, but also for marine life, since it depends so much on the run-off of the soil nutrients that result from the presence of plants.<span> </span>Those few animals that can manage to survive will be done in a few million years by the rising temperatures, for eventually geological processes will bring again significant levels of atmospheric CO<sub>2</sub> , which will no longer be kept in check by photosynthetic organisms.<span> </span>Several scenarios have been proposed to explain what will happen after that point.<span> </span>Likely, the expected increasing level of solar energy, coupled with high levels of atmospheric CO<sub>2</sub>, will quickly lead to the sort of runaway greenhouse effect that vaporized Venus’ oceans.<span> </span>Thus life will come to an end billions of years before the sun’s transition to a red giant obliterates the atmosphere and the oceans altogether.</span></p> <p class="MsoNormal" style=""><span style="font-size: 12pt;"><span> </span>In those perilous days the full development of space exploration will come to humankind’s rescue.<span> </span>It could, for example, “terrraform” its own home planet so it will adjust to the new conditions.<span> </span>When that is no longer feasible because the sun’s sphere will expand beyond Venus, we might be able to change the Earth’s orbit.<span> </span>And on failing that, humankind will hang on, on terraformed Mars and Titan, as well perhaps on artificial worlds along the lines of Gerard O’Neill’s space colonies.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__edn9" name="13134c80e5813d9c__ednref9" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[9]</span></span></span></span></a><span> </span>As humanity expands in search of resources in the solar system, the size and complexity of its space habitats is likely to increase.<span> </span>Eventually our species may move into the Oort Cloud.<span> </span>We will then have followed in space the example of expansion set by our ancestors in our own planet.<span> </span>To accomplish that will require many but plausible advances in propulsion systems, with concomitant increases in the speed of travel.<span> </span>Under those conditions, migration from the Oort Cloud to the stars may well be possible.<span> </span>Humankind will then be able to survive in the truly long run. </span></p> <p class="MsoNormal" style="text-indent: 0.5in;"><span style="font-size: 12pt;">Eons before then, a large human <span style="color: black;">presence will make it easier to track, and then to deflect asteroids and comets </span>most in danger of colliding with the Earth, thus saving millions of human lives, and even preventing a repeat of the global catastrophe that wiped out the dinosaurs and most other life 65 million years ago.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__edn10" name="13134c80e5813d9c__ednref10" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[10]</span></span></span></span></a></span></p> <p class="MsoNormal" style="text-indent: 0.5in;"><span style="font-size: 12pt;"> </span></p> <p class="MsoNormal" style="text-indent: 0.5in;"><span style="font-size: 12pt;"><span> </span>It all begins with astronauts.</span><span style="color: black;"></span></p> <p class="MsoNormal"> </p> <div><br /> <hr align="left" size="1" width="33%"> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__ednref1" name="13134c80e5813d9c__edn1" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[1]</span></span></span></span></a> Tracy Watson, “NASA Chief: Shuttles were a Mistake,” reprinted from <i>USA Today</i> in <i>Detroit Free Press</i>, September 28, 2005, p. 13A.</p> </div> <div> <p class="MsoNormal"><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__ednref2" name="13134c80e5813d9c__edn2" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[2]</span></span></span></span></a> See S.G. Brush, "Harold Urey and the Origin of the Moon: The Interaction of Science and the Apollo Program," in the <i>Proceedings of the Twentieth Goddard Memorial Symposium</i>, 1982, published by the American Astronautical Society; and "From Bump to Clump: Theories of the Origin of the Solar System 1900-1960," in P.A. Hanle and V.D. Chamberlain, eds. <i>Space Science Comes of Age: Perspectives in the History of the Space Sciences</i>, Smithsonian Institution Press, 1981, pp.78-100.<span style="font-size: 12pt; font-family: Courier; color: black;"></span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__ednref3" name="13134c80e5813d9c__edn3" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[3]</span></span></span></span></a> The Constellation program, which NASA has proposed for returning to the Moon is a high-tech update of the Apollo program.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__ednref4" name="13134c80e5813d9c__edn4" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[4]</span></span></span></span></a> <a href="http://www.califcity.com/space_ship_1.html" target="_blank">http://www.califcity.com/<wbr>space_ship_1.html</a></p> </div> <div> <p class="MsoNormal"><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__ednref5" name="13134c80e5813d9c__edn5" title=""><span><span style="color: black;"><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif"; color: black;">[5]</span></span></span></span></span></a> <span lang="EN"><a href="http://www.nasa.gov/mission_pages/gpb/index.html" target="_blank">www.nasa.gov/mission_pages/<wbr>gpb/index.html</a> <span style="color: black;"></span></span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__ednref6" name="13134c80e5813d9c__edn6" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[6]</span></span></span></span></a> See, for example, James E. Oberg, <i>New Earths</i>, Stackpole Books, 1981.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__ednref7" name="13134c80e5813d9c__edn7" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[7]</span></span></span></span></a> J.E. Lovelock and M. Whitfield. 1982.<span> </span>“Life Span of the Biosphere.” <i>Nature</i> 296, pp. 561-563.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__ednref8" name="13134c80e5813d9c__edn8" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[8]</span></span></span></span></a> This account is borrowed from Peter D. Ward and Donald Brownlee, <i>The Life and Death of Planet Earth</i>, Times Books, 2002, pp. 101-116.</p> </div> <div> <p class="MsoNormal"><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__ednref9" name="13134c80e5813d9c__edn9" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[9]</span></span></span></span></a> See Gerard O'Neill's <i>The High Frontier</i>, Anchor Press/Doubleday, 1982 (2nd edition).<span> </span>See also T. Heppenheimer, <i>Colonies in Space</i>, Stackpole Books, 1977.</p> </div> <div> <p class="MsoNormal"><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#13134c80e5813d9c__ednref10" name="13134c80e5813d9c__edn10" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[10]</span></span></span></span></a> The probability of such collisions can be found Dana Desoinie<span style="font-family: "WP TypographicSymbols";">’</span>s <i>Cosmic Collisions</i>, a Scientific American Focus Book, Henry Holt & Co., 1996, pp. 100-101. Thermonuclear weapons are the first choice, although O<span style="font-family: "WP TypographicSymbols";">’</span>Neill<span style="font-family: "WP TypographicSymbols";">’</span>s mass drivers might also do the job.<span> </span>He envisioned using such drivers to transport asteroids rich in valuable minerals to a lunar orbit, <i>op.cit</i>.</p> </div> </div> </div></div><img class="mL" src="https://mail.google.com/mail/images/cleardot.gif" alt="" />Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-46804463062513566512011-07-08T22:16:00.000-07:002011-07-08T22:18:21.577-07:00Robots in Space<div id=":64" class="ii gt"><div id=":65"> <h2><b><span style="font-family: "Times New Roman","serif"; font-style: normal;">Chapter 7B </span></b></h2> <h2><b><span style="font-family: "Times New Roman","serif"; font-style: normal;">Robots in Space<span> </span></span></b></h2> <h2><b><span style="font-family: "Times New Roman","serif"; font-style: normal;"> </span></b></h2> <h2><span style="font-family: "Times New Roman","serif"; font-style: normal;">In this posting I will continue with the critique of manned exploration.<span> </span>In the next posting I will include a response that aims to make a case for manned exploration.<span> </span>Before getting to the case for robots in space, I should mention, in connection with the previous posting, that the newest think about teleoperators will have the operator wear a sort of exoskeleton.<span> </span>As the exoskeleton moves, so does the machine in outer space.</span></h2> <p class="MsoNormal"> </p> <p class="MsoNormal"> </p> <h2><span style="font-family: "Times New Roman","serif";"> Robotics</span></h2> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;">The other hope of the opponents of manned spaceflight is the development of intelligent machines.<span> </span>As those critics constantly remind us, computers can already perform better than humans in several areas.<span> </span>One such area is in geology itself – apparently in contradiction to my earlier remark – where expert programs do a better job in the exploration of underground oil deposits.<span> </span>All we need to do is develop expert programs about the solar system and we will produce robot spacecraft that can do the exploration for us.<span> </span>It may be more heroic to do it with humans, but, according to the critics, at those prices we can afford a bit less heroism and a lot more common sense.<span> </span>Some NASA officials fear that unmanned programs will not enjoy as much public support.<span> </span>In their view, the public derives great satisfaction from the vicarious participation in the grand adventure of space exploration. But opponents of manned exploration argue that robots will permit vicarious participation by the general public in the unraveling of the mysteries of the solar system.<span> </span>We have already experienced that pleasure with the Viking landings and the recent rovers on Mars, with the Voyager missions to Jupiter and Saturn, the Galileo spacecraft, and more recently with Cassini’s visit to Saturn and Titan.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>There is no question that our exploration of the solar system will be more fruitful the more independent and flexible our spacecraft become.<span> </span>But we should not turn this reasonable wish into wishful thinking. The truly successful expert programs are very few; and the successful ones have very limited applications.<span> </span>The spacecraft cannot take expert programs for every contingency unless the mission is rather simple and we have a fair idea of what those few contingencies may be.<span> </span>An expert program, whether for diagnosing diseases or finding oil, works by compiling a large set of techniques and rules of thumb used by the human experts in the field.<span> </span>The programmer discovers what rankings and relative values those human experts give to those techniques and rules of thumb in typical cases of application.<span> </span>Such a program can thus do a better job than an individual human expert because the computer can keep track of a larger number of considerations.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1310d4d436cdaa5e__edn1" name="1310d4d436cdaa5e__ednref1" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[1]</span></span></span></span></a><span> </span>But when the situation is not typical, when it demands different rankings and values, as it is normally the case with the scientific exploration of the unknown, then the expert program soon exhausts its usefulness. Nor can we program in advance those different assignments of rankings and values, precisely because their appropriateness will be determined by unknown circumstances.<span> </span>This is not to say that human beings seldom make mistakes in the way they grasp the situation. Nonetheless, their flexibility does give them an edge where they meet an open-ended environment.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>This problem of flexibility is perhaps the greatest barrier to artificial intelligence.<span> </span>There are many programs that perform very well in restricted domains, but no one has an inkling of how to make a program of general application.<span> </span>All too often what from a distance seems to be a difference in degree that can be overcome with larger computing power and memory storage, up close becomes an insuperable difference in quality.<span> </span>The things that computers cannot do are those like using language or going shopping that come so naturally for even the dullest of human beings. Live intelligence constructs a world for itself, i.e., “interprets” the world as it interacts with it. <span> </span>But being able to tell that much does not amount to knowing how it all works, and thus we are certainly in no position to provide electronic equivalents.<span> </span>We have no idea how to make a computer with the world smarts of a dodo.<span> </span>Newspaper headlines about the wonderful things robots will be able to do in ten years or less are simply pipe dreams that cannot be backed up by any actual research in artificial intelligence.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1310d4d436cdaa5e__edn2" name="1310d4d436cdaa5e__ednref2" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[2]</span></span></span></span></a> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>Whether this barrier can be overcome in principle I will not discuss here.<span> </span>For our purposes, the important consequence is that we have no reason to suppose that it will happen in the next decade or so. <span> </span>It is true that we have often achieved what pundits had declared impossible.<span> </span>The space program is one of our very best examples of that.<span> </span>But the history of our scientific civilization is also full of projects that we later discovered could not be realized.<span> </span>Among those projects we should include the proposals made in their youth by Tsiolkovsky, Goddard, and Oberth, the three pioneers of space flight, for a machine that could lift itself into orbit by its self-generated centrifugal force. As it turned out, the device violated the law of conservation of momentum. </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>In any event, the success of artificial intelligence is not likely to come soon enough to contribute with robots what humans have to offer now to the progress of space science.<span> </span>Where it is inconvenient for humans to go, we must settle for what robots and teleoperators can do.<span> </span>But where we already know that humans can deliver the goods, it is not reasonable to snub them in favor of an uncertain technology. These remarks are not intended to argue against the development of more sophisticated teleoperators and robotics.<span> </span>On the contrary: There are many environments where humans cannot yet go, and will not go for a long time, and others where they should never go.<span> </span>If machines can go in our stead to those environments, we are so much further ahead.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>Nevertheless, opponents of manned flight take a look at the costs of the International Space Station (about $130 billion) and point out that a lot of space science could be done for that amount.<span> </span>For example, the NEAR mission to investigate Eros, an asteroid that comes as close to the Earth as 14 million miles, had a price tag of about $211.5 million dollars, which is pretty standard nowadays.<span> </span>Apart from its scientific value, this mission may someday allow us to figure out how to divert from our planet a similar asteroid.<span> </span>It seems incongruous that for the price of <i>one space station</i> we could fly instead <i>between 400 and 500 interplanetary missions</i>!</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>Let us consider some of the important missions, scientifically and otherwise, whose funding has been affected by the diversion of monies into what some believe is a manned sinkhole in the sky:</span></p> <ol style="margin-top: 0in;" start="1" type="1"><li class="MsoNormal" style="color: black;"><span style="font-size: 12pt;">NASA’s “system of environmental satellites is at risk of collapse”<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1310d4d436cdaa5e__edn3" name="1310d4d436cdaa5e__ednref3" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[3]</span></span></span></span></a> because the agency has shifted to the Shuttle and the Space Station $600 million from the Earth sciences.</span></li><li class="MsoNormal" style="color: black;"><span style="font-size: 12pt;">NASA, for similar budgetary reasons, has downsized the next generation of the National Polar-Orbiting Operational Environmental Satellite System.<span> </span>In particular, it has stripped out “instruments crucial to assessing global warming, such as those that measure incoming solar radiation and outgoing infrared radiation.”<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1310d4d436cdaa5e__edn4" name="1310d4d436cdaa5e__ednref4" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[4]</span></span></span></span></a></span></li><li class="MsoNormal" style="color: black;"> <span style="font-size: 12pt;">For $100 million of fine-tuning the Large Synoptic Survey Telescope (LSST) we could identify 90 percent of asteroids between 100 and 1000 meters in size.<span> </span>And since the LSST is Earth-bound and thus is limited (can spot the asteroids the come closest only at dusk or dawn, when the sun’s glare may obstruct our vision of them), for $500 million we could place in orbit around the sun an infrared telescope that “could pick up essentially every threat to Earth.”<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1310d4d436cdaa5e__edn5" name="1310d4d436cdaa5e__ednref5" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif"; color: black;">[5]</span></span></span></span></a></span></li><li class="MsoNormal" style="color: black;"> <span style="font-size: 12pt;">For $400 million, the proposed Don Quijote would fire a 400 kg projectile into a small asteroid to see how it affects its trajectory.<span> </span>This would begin to help us figure out how to deflect asteroids bound to collide with our planet.<span> </span></span></li><li class="MsoNormal" style="color: black;"> <span style="font-size: 12pt;">An orbiter around Europa could determine once and for all whether that Jovian moon really has an ocean.<span> </span>A wandering hot-air balloon in the atmosphere of Titan can tell us whether there are traces of self-organization by the organic substances found there by the Cassini mission.<span> </span>Given NASA’s need to pump money into manned exploration, the agency will have to choose between these two missions. Shouldn’t we do both?</span></li></ol> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>These examples were current as of 2008; by now new cuts in space budgets will probably make the situation worse. Nevertheless, they still give us an inkling of how far space science could go if not for our mania to send humans into space.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>When the space station was first proposed, most space scientists feared, with good reason, that, on the whole, the space station was going to take money away from space science.<span> </span>I say with good reason because that is exactly what happened during the construction of the Space Shuttle.<span> </span>As the new vehicle could not be brought in under budget, the space sciences suffered a double jeopardy.<span> </span>First, their funds for many science projects were transferred to the shuttle.<span> </span>And then many experiments were not performed because they had been scheduled to go in the shuttle but the shuttle was not ready.<span> </span>The two shuttle disasters made the situation a lot worse. Money has and will continue to be drained from the space sciences to keep astronauts flying (to accomplish very little science by comparison).<span> </span>It was quite proper for scientists to want to ensure that a commitment to the space station would not be underwritten on the back of space science.<span> </span>Now we can see that their worst fears have been realized.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span></span><span style="font-size: 12pt;">According to the bioengineer and NASA adviser Larry Young, “NASA always uses research as justification for its large manned missions, but once they are under way the engineering, political, and fiscal factors take over and the science constituency is often cast aside.”<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1310d4d436cdaa5e__edn6" name="1310d4d436cdaa5e__ednref6" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[6]</span></span></span></span></a> Weinberg is far bitter:<b> </b><span>Of five missions proposed to challenge and expand Einstein’s General Theory of Relativity, only one is likely to survive. </span>"This is at the same time,” he says, “that NASA's budget is increasing, with the increase being driven by what I see on the part of the president and the administrators of NASA as an infantile fixation on putting people into space, which has little or no scientific value."<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1310d4d436cdaa5e__edn7" name="1310d4d436cdaa5e__ednref7" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[7]</span></span></span></span></a><span> For Weinberg, what has happened to the Beyond Einstein program reminds him of the time when the most grandiose particle-physics project, the</span> Superconducting Super Collider, which was being built in Texas, was scrapped by Congress because funds were needed to build the International Space Station.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>It should not be surprising, then, that a great many space scientists are now opposed to the new proposals to send humans back to the Moon and on to Mars.<span> </span>And we cannot blame them for, as we have seen, money is already beginning to drain from unmanned exploration.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>As for the disadvantages of teleoperators and robots, the opponents of manned exploration point out, we can send dozens of dumb robots or clumsy tele-operated contraptions to take on the sundry jobs a human could theoretically do in space.<span> </span>Certainly, we will fail far more often, but the failures will not be as costly or devastating; we will save money; we will get the job done; and we will be forced to improve our science and technology.<span> </span>It is not just that we can try with machines again and again until we get it right, but also that we can divide the tasks humans would have performed into many simpler tasks and then try to accomplish those with swarms of new machines.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>And let us not forget that machines have traveled tens of thousands of times further than humans have ever gone.<span> </span>What sense does it make to restrict exploration to dipping our toes when we could swim across the English Channel?</span></p> <p class="MsoNormal"> </p> <div><br /> <hr align="left" size="1" width="33%"> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1310d4d436cdaa5e__ednref1" name="1310d4d436cdaa5e__edn1" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[1]</span></span></span></span></a> Hoegland, John.<span> </span><i>Artificial Intelligence: The Very Idea</i>, MIT Press, 1985.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1310d4d436cdaa5e__ednref2" name="1310d4d436cdaa5e__edn2" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[2]</span></span></span></span></a> This point was made as early as 1972 by Hubert Dreyfus in his <i>What Computers Can’t Do: A Critique of Artificial Reason</i>, <span style="color: black;">Harper & Row.</span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1310d4d436cdaa5e__ednref3" name="1310d4d436cdaa5e__edn3" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[3]</span></span></span></span></a> This and most of the examples that follow are taken from George Musser, “5 Essential Things to do in Space,” <i>Scientific American</i>, October 2007, pp. 75. The present quote is from p. 70.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1310d4d436cdaa5e__ednref4" name="1310d4d436cdaa5e__edn4" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[4]</span></span></span></span></a> <i>Ibid</i>.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1310d4d436cdaa5e__ednref5" name="1310d4d436cdaa5e__edn5" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[5]</span></span></span></span></a> <i>Ibid</i>, p. 71.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1310d4d436cdaa5e__ednref6" name="1310d4d436cdaa5e__edn6" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[6]</span></span></span></span></a> <i>Science</i>, Vol. 310, 25 November 2005, p. 1245.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1310d4d436cdaa5e__ednref7" name="1310d4d436cdaa5e__edn7" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[7]</span></span></span></span></a> SPACE.com, <i>op. cit</i>.</p> </div> </div> </div></div>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-23251732070199180772011-07-02T20:24:00.000-07:002011-07-02T20:26:30.098-07:00HUMANKIND IN OUTER SPACE<div id=":6o" class="ii gt"><div id=":6p"> <p class="MsoNormal">CHAPTER 7A</p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;">HUMANKIND IN OUTER SPACE</span></p> <p class="MsoNormal" style="text-align: center;" align="center"><span style="font-size: 12pt; line-height: 115%; color: black;"> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%;">The famous scientist Steven Weinberg, 1979 physics Nobel Laureate, claimed that “the whole manned spaceflight program, which is so enormously expensive, has produced nothing of scientific value."<span> </span>This remark capped a scathing critique in which he also said that "The International Space Station is an orbital turkey…. No important science has come out of it. I could almost say no science has come out of it.”<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130ec52aaa610ee8__edn1" name="130ec52aaa610ee8__ednref1" title=""><span><span><span><span style="font-size: 12pt; line-height: 115%;">[1]</span></span></span></span></a> And a New York Times columnist reportedly stated matter-of-factly that “Three decades after going to the moon, NASA is sending astronauts a few hundred miles above Earth to conduct high school science experiments.”<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130ec52aaa610ee8__edn2" name="130ec52aaa610ee8__ednref2" title=""><span><span><span><span style="font-size: 12pt; line-height: 115%;">[2]</span></span></span></span></a> Nor is the value of manned exploration likely to change, for according to Weinberg, "Human beings don't serve any useful function in space," he told <i>SPACE.com</i>. "They radiate heat, they're very expensive to keep alive and unlike robotic missions, they have a natural desire to come back, so that anything involving human beings is enormously expensive." <span style="color: black;">This derisive view of manned exploration is widespread amongst space scientists themselves.<span> </span>Indeed space scientists are likely to object bitterly to projects like the space station and President Bush’s proposals to send humans to the Moon and eventually to Mars.<span> </span>My sympathies are with those scientists: Manned exploration has indeed been detrimental to space science.<span> </span>And in the short run it will continue to be so.<span> </span>But in the long run manned exploration will help greatly the cause of space science while providing great benefits to the human species.</span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;"><span> </span><span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;">MANNED VS. UNMANNED EXPLORATION: THE NEAR FUTURE</span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;"> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;">Some space scientists argue that we can achieve the goals of space science better with machines than with astronauts.<span> </span>Their feeling is that the money and effort that could be spent on driving science and technology to explore the cosmos is in large part lost when we concentrate instead on ensuring the safety of astronauts and on developing very expensive and cumbersome life-support systems.<span> </span>An astronaut needs air, water, food, and protection from a hostile environment. The satisfaction of these needs requires bigger rockets to handle the far heavier payloads – as well as far more reliable spacecraft.<span> </span>A human being is a delicate creature.<span> </span>Even with the best of our technology we could not easily send astronauts into the hell of Venus or the intense radiation of Jupiter's vicinity.<span> </span>A trip to Mars would also be very difficult, since it would take months under constant bombardment from the solar wind, enough to destroy upwards of ten percent of the astronauts' brain cells unless the spacecraft is especially protected – in addition to the possible adverse physiological effects from such a long exposure to weightlessness.<span> </span>Machines, on the other hand, can go practically everywhere in the solar system, for far less money.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;"><span> </span>Proponents of manned spacecraft reply that humans can do many things that machines cannot.<span> </span>For example, humans can perform experiments that require great dexterity, and they can retrieve and fix satellites.<span> </span>That is true, but according to their critics, not relevant.<span> </span>First, machines can do their more limited job in places where humans cannot or should not do any job at all.<span> </span>This includes not only trips of very long duration and hazardous environments, but also dangerous experiments. Second, in many space science experiments the presence of man is a hindrance.<span> </span>For example, telescopes have to be so precisely aimed that someone moving around in the spacecraft would disturb the observations.<span> </span>Third, even if astronauts can retrieve and fix satellites, and build and operate industrial facilities, whereas present machines cannot, we can design our space equipment so robots or teleoperators could handle the job. This of course requires that we develop robots and teleoperators equal to the task.<span> </span>Thus on the whole, the impetus that technology receives is greater from exploring space with machines than from worrying about the safe transportation of astronauts.<span> </span>Furthermore, advances in machine operations in low orbit can be applied throughout the solar system, whereas astronauts will be unlikely to venture beyond Mars in the next fifty years, and even that looks to the critics like pie in the sky (pun intended).</span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;"><span> </span>The tragic destruction of two Space Shuttles, Challenger and Columbia, threw into disarray the space program and has done great harm to space science. They have clearly shown the risks both to human life and to science from too great a reliance on manned exploration.<span> </span>Indeed, even when the space shuttle flies normally, space science suffers, and, as we will discuss below, the space station makes matters worse. Why should we then insist on manned exploration when we can accomplish far more, and to do it far more cheaply, safely and efficiently with machines?</span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;"> </span></p> <h1><span style="font-family: "Times New Roman","serif";">Exploring with Machines</span></h1> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;"> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;">Let us take a look at the two main technologies favored by the critics of manned exploration: robotics and teleoperators.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;"> </span></p> <h2><span style="font-family: "Times New Roman","serif";">Teleoperators</span></h2> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;"> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;">Teleoperators permit us to handle via radio and television tasks that must be carried out at a distance.<span> </span>For example, a television camera on a machine transmits to the ground an image of two building blocks, and a human operator makes the arms in the machine put the two blocks together by radio transmission.<span> </span>Interaction between ground crews and a variety of orbiting observatories has actually become routine.<span> </span>We can change orbits, aim cameras and telescopes, and even perform experiments.<span> </span>An advance in the various aspects of teleoperators -- sensors, arms, fingers, grip, and dexterity -- will increase the range of activities that we can perform by remote control in space.<span> </span>Teleoperators combined with robotics can go even further: The human operator would perform certain repairs, say, in a comfortable laboratory, while a robot would mimic the same actions in a far more hostile environment.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130ec52aaa610ee8__edn3" name="130ec52aaa610ee8__ednref3" title=""><span><span><span><span style="font-size: 12pt; line-height: 115%; color: black;">[3]</span></span></span></span></a></span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;"><span> </span>But some serious problems remain.<span> </span>The most obvious problem is that the farther away the spacecraft is, the harder it is to run it by remote control. Imagine that a roving vehicle on the Moon comes suddenly upon a hole or an unexpected rock.<span> </span>Its television camera will immediately send a picture of the obstacle to an operator on Earth.<span> </span>But on the average it takes that signal one and a half seconds to arrive.<span> </span>If the human operator reacts instantly, the instruction will arrive at the Moon one-and-a-half seconds after that.<span> </span>Any one who has driven a car knows very well that many disasters can be crammed into three seconds, which is the minimum time that it would take for the earthbound human operator to react to the lunar environment.<span> </span>For a rover on Mars that time would be of the order of eight to forty minutes, and for the outer planets we have to allow hours.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;"><span> </span>There are two ways to reduce this difficulty.<span> </span>One is to anticipate as much as possible and build our space machines accordingly.<span> </span>We could, for example, provide the lunar vehicle with a computer map of the land it must travel (drawn from photographs taken by orbiting spacecraft).<span> </span>Any deviation from that landscape will automatically force it to stop until it receives fresh instructions from its human operator.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;"><span> </span>On the Earth, of course, an attentive human driver is able to detect a nasty pothole and get out of harm's way in less than three seconds. But to do so he uses a variety of perceptual clues that allow him to spot a hole for what it is and to tell just how far it is.<span> </span>The teleoperator, by contrast, is looking trough a television camera at an alien landscape: his remote vision is poorer than the terrestrial driver’s, and he does not have all the perceptual clues that his perceptual apparatus needs to come to a quick decision.<span> </span>The upshot of all this is that the roving vehicle must move very slowly.<span> </span>That is so even when the terrain is reasonably well known.<span> </span>When the vehicle is called upon to do some honest-to-goodness exploration, the difficulty becomes acute.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;"><span> </span>As a matter of fact, the Russians sent one such vehicle to the Moon. And NASA had plans for another at one time.<span> </span>But when the best hopes for its performance were so clearly surpassed by the actual performance of the astronauts, the project – called "Prospector" – died of natural causes.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;"><span> </span>The teleoperator is then at a disadvantage with respect to a human on the spot, at least for certain kinds of jobs.<span> </span>Not only is his camera not as good as a human eye, it does not receive the correcting feedback of the other human senses. Human beings do not just see what is out in the world and correctly report it to consciousness.<span> </span>They pick out and concentrate instead on a variety of subtle clues as to what is most relevant and worthy of attention.<span> </span>A human observer looking through a television camera has fewer of those clues (he will be missing clues that are peripheral, in the background, or correlated with hearing, smell, or touch).<span> </span>Even if he is highly trained, in a new situation his degraded experience may not suffice for him to recognize objects and situations in the way he has been trained to do.<span> </span>A laboratory biologist can tell at a glance that a guinea pig is ill because somehow its behavior differs subtly from patterns to which the biologist responds even if he cannot describe them. It is our hands-on experience that allows us to gain what appears to be an intuitive "feel" for our surroundings.<span> </span>Geologists and materials experts may also depend on the immediacy of contact in order to grasp the object of study in this quasi-intuitive way.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;"><span> </span>In space, it is true, many of the associations between the senses may be disturbed by the absence of gravity, and thus previous training may lead a scientist on the spot to misjudge the situation.<span> </span>But human beings have the capacity to adapt and to form new associations.<span> </span>A biologist making slides of a rat's brain can learn how to compensate for the new environment.<span> </span>The teleoperator, on the other hand, faces two different problems.<span> </span>First, at present his artificial “hand” simply does not have the dexterity to carry out that refined a task.<span> </span>Second, even if it did, and eventually it might, he could not use that artificial hand the way he would on Earth; he would have to be retrained so as to make that artificial hand do from Earth what the biologist does with his real hand in space.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;"><span> </span>To make a better artificial hand (or other appropriate tools) it would be wise to observe what the human biologist does in his space laboratory, and then slowly refine the technology until it is acceptable.<span> </span>Cutting a rat’s brain in weightlessness may be quite different from doing it on the surface of the Earth.<span> </span>It makes sense, then, first to try to learn what it is like to do that kind of lab work in space.<span> </span>That is, we need to develop a space expertise in those activities – a human expertise.<span> </span>Only then we might be in a position to calibrate our teleoperations.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;"><span> </span>The obvious conclusion of all this is that teleoperating technology is best developed in cooperation with human activity in the relevant areas.<span> </span>To perform at the level that the proponents of unmanned flight hope for, we would require to have a joint, and to some degree a prior human presence in space. This might be a useful technology to develop in the International Space Station.<span> </span>Although a space station is not very useful to all branches of space science, it may be very valuable to biology, materials processing and medical technology. Moreover, as our experience with the Shuttle has demonstrated, there are experiments in physics that require a high degree of finesse or complexity in the handling from space (for example, electron beam experiments to examine the interaction of charged particles with the Earth's magnetic field).<span> </span>Without the mission and payload specialists in the spacecraft, those experiments could not have taken place for decades, if at all.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; line-height: 115%; color: black;"><span> </span>For materials processing, one of the most promising areas of space industrialization, artistry is as crucial as scientific craft.<span> </span>We must not forget that the initial purpose of the space station, apart from science, is to do industrial research rather than to set up actual industries.<span> </span>If it were the latter, then there might be some hope for combining teleoperators and a high level of automation.<span> </span>But insofar as the purpose is largely one of exploration, the machine technology is not yet up to the challenge.<span> </span>Nor are our teleoperating abilities so developed that we could build those completely automated factories without the help of human workers in space.</span></p> <p class="MsoNormal"> </p> <div><br /> <hr align="left" size="1" width="33%"> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130ec52aaa610ee8__ednref1" name="130ec52aaa610ee8__edn1" title=""><span><span><span><span style="font-size: 10pt; line-height: 115%; font-family: "Times New Roman","serif";">[1]</span></span></span></span></a> Kerr Than, <a href="http://www.space.com/" target="_blank">www.space.com</a>, September 8, 2007.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130ec52aaa610ee8__ednref2" name="130ec52aaa610ee8__edn2" title=""><span><span><span><span style="font-size: 10pt; line-height: 115%; font-family: "Times New Roman","serif";">[2]</span></span></span></span></a> Reported by John Tierney, “Outer Space on Earth: NASA Should Try It,” reprinted in <i>Detroit Free Press</i>, August 2, 2005, p. 7A.<span> </span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130ec52aaa610ee8__ednref3" name="130ec52aaa610ee8__edn3" title=""><span><span><span><span style="font-size: 10pt; line-height: 115%; font-family: "Times New Roman","serif";">[3]</span></span></span></span></a> Gilster, Paul (2002). <i>Centauri Dreams</i>, Copernicus Books, p. 216.</p> </div> </div> </div></div>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-75784469719450024182011-06-23T22:32:00.000-07:002011-06-23T22:34:23.134-07:00LIFE IN SPACE: THE COMPLETE STORY?<div id=":6l" class="ii gt"><div id=":6m"> <p class="MsoNormal"><b><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">Chapter 6L</span></b></p> <p class="MsoNormal"><b><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"> </span></b></p> <p class="MsoNormal"><b><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">LIFE IN SPACE: THE COMPLETE STORY?</span></b><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">Astrobiology and what I have called space biology proper do not exhaust the possibilities that space offers to the life sciences. Those possibilities extend to many areas in which our understanding of life may have profound consequences for our interaction with nature.<span> </span>I would like to conclude this chapter by considering briefly three novel areas of investigation.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>The first may be called planetary biology, or perhaps global biology.<span> </span>So far I have discussed our attempts to understand micro-organisms, plants, and animals. But we also wish to understand the living environment as a whole and in relation to the other components of the global environment. Planetary biology attempts to achieve this by means of interdisciplinary research that makes extensive use of space techniques for atmospheric sampling and remote sensing. From the remarks made in Chapter 4 it is clear that the study of the role of bacteria and plants in the global environment fits in nicely with the aims of planetary science.<span> </span>Planetary biology expands the scope of investigation and makes the relationship to general planetary science all that more evident. One of its initial aims is to trace the flow of nitrogen and sulfur in the marine environment off the coast of California, and to determine the mechanisms by which different compounds of these elements are converted into others.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130c01a16088b181__edn1" name="130c01a16088b181__ednref1" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[1]</span></span></span></span></a> The eventual goal of this new field is quite ambitious. In Harold Klein's words, it is "to treat the planet as an ecosystem and try to understand the laws of this ecosystem."<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130c01a16088b181__edn2" name="130c01a16088b181__ednref2" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[2]</span></span></span></span></a></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>A second area of investigation involves the construction of closed environments in space. Until now we have not built any really closed environments up there -- natural wastes are thrown into space, not recycled as on the Earth, oxygen is lost to the vacuum, and so on.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130c01a16088b181__edn3" name="130c01a16088b181__ednref3" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[3]</span></span></span></span></a> Furthermore, the balance of those environments is maintained by artificial means. Whether we can ever built living closed environments in space is a matter of controversy.<span> </span>Indeed, at this time we cannot even determine the minimum size required for a naturally self-sustaining environment amenable to Earth life.<span> </span>But in trying to build one we may learn much.<span> </span>In fact, even artificially closed environments may teach us valuable lessons about terrestrial ecology.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>There are several obstacles that limit severely the knowledge we can obtain about an ecological system.<span> </span>One of them is that the amount of variables involved, most of which are interrelated, is simply unmanageable.<span> </span>And even when this obstacle is overcome, the victory seldom lasts long.<span> </span>Normally, a model of a system accounts for changes in one part of the system by changing the amount of reaction in other parts. More sophisticated models may go as far as predicting the rate of such reaction. The problem is that, when confronted with different circumstances, organisms sometimes change not just the amount and rate but the <i>modality</i> of reaction.<span> </span>This problem is illustrated by two examples from a report of the National Academy of Sciences entitled <i>Life Beyond the Earth's Environment</i>: "...many bacteria will use available nitrogen if it is present but in its absence become fixers of nitrogen from the air. Brown hydra in competition with green hydra will, in the presence of abundant food, eat their competitors, and in the absence of abundant food, will float away to some new location leaving the area to the green hydra alone."<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130c01a16088b181__edn4" name="130c01a16088b181__ednref4" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[4]</span></span></span></span></a></span></p> <p><span style="font-family: "Geneva","serif";"><span> </span>Another problem is that a complete description of an ecosystem often requires that we count the numbers of each kind of organism in order to ascertain what it contributes to the flux of matter and energy of that ecosystem.<span> </span>But such counting, for example of worms in the soil, in many cases destroys the ecosystem we are merely trying to describe.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>A suggestion for getting around these problems is that we test models of the system in closed versions of it.<span> </span>These models would not attempt to represent every element of the system -- which would be practically impossible -- but would be based instead on a list of the species present and on the roles played by the species presumed to dominate the system.<span> </span>The suggestion is that we build closed environments in accordance with one such model, and then partition them in a variety of ways.<span> </span>We can learn from the interruptions in the normal flows and cycles of the system what its crucial factors are. By disturbing or interrupting the cycle of nutrients, for example, many species may starve while their food accumulates elsewhere, and others may be poisoned by the concentration of toxic wastes that normally would have been washed away. Of course, these partitions do not only take away from the system, in some cases they add to it; just as a dam that interrupts the flow of a river creates a habitat favorable to a variety of organisms that would have been at a disadvantage otherwise.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>Intelligent manipulation of this ecology of failure offers the prospect of many exciting questions and experiments.<span> </span>But on Earth there are two serious limitations. One is that the only completely closed system is the Earth itself, which, though open to energy, is relatively closed to matter. Partial closure is of course satisfactory for many investigations, but in some cases we may need greater experimental control. Another limitation is that some closures may be dangerous or undesirable (they may produce very toxic substances, for example).<span> </span>Space offers an opportunity to achieve perfect closure in many investigations that cry out for it; it also permits us to carry out some of the most dangerous experiments in capsules safely isolated from our home planet.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>An apparent limitation of space is that larger and richer environments cannot be easily recreated. But there is a sense in which this limitation becomes an advantage.<span> </span>An increased manned presence in space means a greater complexity of man-made habitats, perhaps with a serious attempt to create space agriculture.<span> </span>But this would automatically require that as the ecosystem gets larger we learn more and more about what the crucial flows and cycles are and what it takes to maintain them.<span> </span>A lunar base, for example, can be viewed as an experiment to determine the degree to which environmental sufficiency can be achieved.<span> </span>And a Martian colony may be in a good position to experiment with a variety of environments for agriculture, since the red planet is rich in resources and the colonists may thus have many choices in the composition of such environments.<span> </span>Gerard O'Neill's space colonies may have an even greater potential.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>A third area of promise is the invention of new tools to investigate the basic levels of organisms.<span> </span>This point seldom receives the attention it deserves.<span> </span>The absence of gravity permits the development of experimental techniques that are either very difficult or plain impossible on the surface of the planet. I will mention a few ideas that have been suggested over the years, just to catch the flavor of the possibilities.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>The technique of electrophoresis, which was described in Chapter 2, can become a useful tool for the production of pure drugs.<span> </span>But its real potential may be found in research instead. For example, our metabolic processes are controlled by about 2,000 enzymes, of which as many as one hundred are mixtures of isozymes.<span> </span>With electrophoresis, we can separate and study those isozymes.<span> </span>If nothing else we can vastly improve our diagnostic skills in matters concerning imbalances and disorders of the human body.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>And I think there is reason to believe that this use of electrophoresis in space may herald a new generation of analytical tools for biologists and medical researchers. And that reason is simply that by removing gravity we may not only gain much in purity but also take advantage of the fine operation of electric currents.<span> </span>Some of this fine operation already pays dividends on Earth.<span> </span>Using weak pulsed electric fields, for instance, it is possible to induce cells to fuse, a technique that leads to very unusual new cells.<span> </span>It can be used, among other things, to fuse tumor cells with the spleen cells that produce the specific antibodies that could destroy the tumor if there were only enough of them.<span> </span>The value of one of these fused cells (hybridomas) is that it will make many copies of itself (clones).<span> </span>And all of these copies will produce the same antibody of the original spleen cell, but now in large amounts, we hope, to get rid of the tumor once and for all.<span> </span>I do not know whether this very technique will prove feasible in space.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130c01a16088b181__edn5" name="130c01a16088b181__ednref5" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[5]</span></span></span></span></a><span> </span>But others kindred to it may find in the advantages of space (purity, effective use of weak currents) the right spark to ignite a new explosion in biomedical research.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>Many tools for medical research, and many new medical technologies may come from physics instead.<span> </span>According to an article by John Tierney:</span></p> <p class="MsoNormal" style="margin-left: 0.5in;"><span style="font-size: 12pt;">The Russians invented an air scrubber using strong electric fields and cold-plasma chambers to prevent biological contamination of the air in the MIR space station.<span> </span>Now the French-based firm AirlnSpace, with support from the European Space Agency, have refined the Russian invention to create the portable “Inmunair.”<span> </span>According to the firm’s general manager, the system successfully screened anthrax and small-pox substitutes in laboratory tests.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130c01a16088b181__edn6" name="130c01a16088b181__ednref6" title=""><span><span><span><span style="font-size: 12pt; font-family: "Times New Roman","serif";">[6]</span></span></span></span></a></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>These three areas are mere examples. I have neither the expertise nor the imagination to evaluate all the promise of space biology.<span> </span>Suffice it to say, for now, that space biology is in a position to ask not only new questions but also new kinds of questions.<span> </span>In this, like the rest of space science, it fulfills the function of preserving the dynamic character of science. Some of space biology, the search for origins in particular, merits its pursuit as a main goal. Space biology proper, as I have called it, is in its theoretical and experimental infancy, and will probably have to ride as a passenger of other space undertakings. Nevertheless I have given reasons why it is worth supporting in its own right. For the time being, it can be considered as one of the benefits that come to us from the general exploration of space.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"> </span></p> <p class="MsoNormal"> </p> <div><br /> <hr align="left" size="1" width="33%"> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130c01a16088b181__ednref1" name="130c01a16088b181__edn1" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[1]</span></span></span></span></a> <span style="color: black;">For example, to what extent is dymethyl sulfide produced by marine algae?</span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130c01a16088b181__ednref2" name="130c01a16088b181__edn2" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[2]</span></span></span></span></a> <span style="color: black;">Harold Klein, "The Biological Sciences and NASA," NASA Advisory Council Talk, May 1983, p.5 of the text.<span> </span></span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130c01a16088b181__ednref3" name="130c01a16088b181__edn3" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[3]</span></span></span></span></a> <span style="color: black;">For a discussion of these issues see <i>Life Beyond the Earth's Environment</i>, a report of the Space Science Board of the National Academy of Sciences, 1979 (section in ecology, pp. 105-132); R.M. Mason, J.L. Carden, eds., Controlled Ecological Life Support System: Research and Development Guidelines, NASA CP-2232, 1982; B. Moore III and R.D. MacElroy, Controlled Ecological Life Support System: Biological Problems, NASA CP-2233, 1982; and B. Moore III, R.A. Wharton, R.D. MacElroy, eds., Controlled Ecological Life Support Systems: First Principal Investigators Meeting, NASA CP-2247, 1982.</span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130c01a16088b181__ednref4" name="130c01a16088b181__edn4" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[4]</span></span></span></span></a> <i><span style="color: black;">Life Beyond the Earth's Environment</span></i><span style="color: black;">, ibid., p.111.</span></p> </div> <div> <p class="MsoNormal"><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130c01a16088b181__ednref5" name="130c01a16088b181__edn5" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[5]</span></span></span></span></a> <span style="color: black;">There are three problems with this technique as a weapon against cancer.<span> </span>One is the difficulty in the formation of hybridomas.<span> </span>In this, weak currents offer some advantages over competing technologies.<span> </span>My guess is that these advantages would be even more apparent in microgravity.<span> </span>A second problem is the stability of the hybridomas.<span> </span>In this, the record of microgravity experimentation should offer some encouragement.<span> </span>The third problem is the selection of the appropriate spleen cell to fuse with the tumor.<span> </span>In this, space does not offer special advantages, unless we consider the possibility of refined techniques of separation and identification.</span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#130c01a16088b181__ednref6" name="130c01a16088b181__edn6" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[6]</span></span></span></span></a> John Tierney, “Outer Space on Earth: NASA Should Try It,” reprinted in <i>Detroit Free Press</i>, August 2, 2005, p. 7A.<span> </span>Tierney’s derogatory comments are limited to the Space Shuttle.<span> </span>He does believe that much worthwhile scientific exploration can be done otherwise.</p> </div> </div> </div></div>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com1tag:blogger.com,1999:blog-5232161716029893381.post-63035706944021607462011-06-12T00:16:00.000-07:002011-06-12T00:19:58.622-07:00A Case for Biological Research in Space<div id=":8x" class="ii gt"><div id=":8y"> <p class="MsoNormal"><b><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">Chapter 6K</span></b></p> <p class="MsoNormal"><b><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">A Case for Biological Research in Space</span></b></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">The first general concern about biological experiments in space is that the quality of the research has not been very high.<span> </span>Now, I must admit that there is a clear sense in which this charge is correct: Space biology has not produced any research that would qualify as extremely important.<span> </span>The aim of such research has been to gather the preliminary information that can then serve as the inspiration for hypotheses or as the ground for the testing of ideas.<span> </span>Since, except for the clinical research done for the safety of astronauts, most space biology has taken a back seat to other science, it is not surprising that the information obtained is generally inconclusive and sketchy.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>Let me illustrate the nature of the problem by discussing the study of mammalian development. Ideally we would want to determine the role of gravity by observing whether any of the important stages in development is affected in microgravity.<span> </span>The first thing we have to do is look, then.<span> </span>We must look at copulation, fertilization, initial cleavages, embryonic and fetal stages, and postnatal maturation.<span> </span>Many of these are, of course, divided into several distinct and important stages.<span> </span>But we have never been able to observe mammalian copulation, let alone postnatal maturation.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__edn1" name="1308292f03be78dd__ednref1" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[1]</span></span></span></span></a><span> </span>The flights open to the biologists have been too short for that.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>The situation is better, but not all that much better, with other animals or plants.<span> </span>Fertilized eggs of fish have flown in space.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__edn2" name="1308292f03be78dd__ednref2" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[2]</span></span></span></span></a> <span> </span>These eggs have hatched successfully, whereas frog eggs have not produced tadpoles. <span> </span>And plants have been made to produce seeds.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__edn3" name="1308292f03be78dd__ednref3" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[3]</span></span></span></span></a><span> </span>Unfortunately yields have been low and chromosomal abnormalities common.<span> </span>But some of these results could be accounted for by the stress of flight itself (e.g., the accelerations of take-off and re-entry) or by shortcomings of the life-support systems that make up their artificial space environments.<span> </span>In addition to all that, specimens have normally been examined some time after their return to Earth, when gravity has begun to reverse the effects of its absence.<span> </span>We need to go from seed to seed and from egg to egg -- <i>in space</i>.<span> </span>And we need to do this several times over, so that we can isolate and control factors that belong to the inconveniences of spaceflight other than microgravity. But these multi-generational studies would take months, if not years. And then we also need trained biologists to monitor and examine the specimens in space, where the effects we want to discover take place. Living things must be handled delicately and skillfully if they are to bare their secrets. <span> </span>In more recent flights, the reproductive systems of rats have been damaged, with the ovaries shutting down in females and the testes in males shrinking. </span></p> <p><span style="font-family: "Geneva","serif";"><span> </span>The difference between what needs to be done and what has been available makes space biology appear primitive.<span> </span>To a critic, the space biologist's collections of data may resemble the wasteland of empirical social science.<span> </span>Or as someone might say, it is just Baconian science -- without theoretical direction, and thus without theoretical interest.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>The critic burdens them with a Catch 22, space biologists feel.<span> </span>To show how their field may be significant they must carry out enough investigations so they can begin to ask fruitful questions.<span> </span>But critics object to those investigations on the grounds that space biology has not yet been shown to be significant.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>It may be useful to compare the situation of space biology to that of atomic physics at the beginning of the 20<sup>th</sup> century and to that of particle physics during the 1960s: Physicists would accelerate particles, crash them against targets, and analyze the debris created in the collision (in atomic physics the aim was to determine the structure of atoms by the deflections of the electrons that crashed against them, in particle physics to discover particles and determine their properties).<span> </span>There is a sense in which the particle and atomic physicists were just "fishing," as the space biologists are now accused of doing.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>Critics will no doubt rush to argue that there is a big difference.<span> </span>That difference is presumably is that they were fishing in fundamental waters.<span> </span>Whatever they found would have the most significant consequences.<span> </span>But that is easy to say in hindsight.<span> </span>The proliferation of particles in the 1960s led many to think that further searches -- and extremely expensive searches at that -- would amount to just looking around without any theoretical purpose of note, a Baconian end to a century of exciting physics. As for Rutherford and the other atomic physicists of the turn of the previous century, they were fishing in domains that most other physicists would not even agree were real, let alone significant.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__edn4" name="1308292f03be78dd__ednref4" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[4]</span></span></span></span></a> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>Hindsight is, of course, a wonderful sense.<span> </span>Today we can see that all those particle surveys in the 1960s allowed physicists to classify the particles into families--a classification not unlike that of the chemical table of elements -- and then to propose new theories about the structure of matter.<span> </span>Thus the quark hypothesis and a new era of physics were born.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>In both cases, however, it took great vision to see the promise of the research. Some important physicists did think that Rutherford was onto something. They held the notion that fundamental aspects of nature might be explained by discovering how matter was put together at the most elementary level.<span> </span>Many decades later, after discovering so many elementary particles, physicists generally thought that the problem was how to make sense of the array.<span> </span>And thus what might have looked as hack work from a point of view, from another it seemed as the preliminary taxonomy essential for the physics of the future.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>My point is precisely that space biology should be given the chance to carry out that preliminary taxonomy, even if it looks like hack work to some critics.<span> </span>The warrant for doing so is the same as in the two cases from the history of physics: the theoretical pay-off comes from testing matter well beyond the range that we have examined previously. </span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>This warrant is clearly seen in the case of some sciences.<span> </span>Take space astronomy, for example.<span> </span>Once we could detect the entire electromagnetic spectrum by placing our telescopes and other instruments above the atmosphere, we embarked in a new survey of the heavens.<span> </span>It may have seemed that we are just looking around. But we had good reason to suspect that what we would find would be significant, that our ideas would be challenged to the utmost. And that reason was precisely that we knew how limited our range of observation had been until then. <a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__edn5" name="1308292f03be78dd__ednref5" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[5]</span></span></span></span></a></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>In space biology, unlike space astronomy today, but like space astronomy not long ago, we cannot specify the great scientific rewards that await us.<span> </span>We know, however, that the gravity of the Earth has been a constant throughout the evolution of life.<span> </span>We also know that the more pervasive a constant, the more difficult it is for us to determine its role, if any. That is exactly what happens with gravity. How are we to proceed, then?<span> </span>First of all, we cannot resolve the matter by further standard biological analysis.<span> </span>For in analysis we use the tools of prevailing theory to investigate some phenomena. To discover that role by analysis is therefore practically impossible, since nothing in our previous biology makes gravity a crucial element of the theory.<span> </span>What we need is either an alternative theory in which gravity is assigned a specific role, or else the manipulation of gravity to make present theory fail.<span> </span>We can do both.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>These new theoretical and experimental directions are suggested in part by some of the early results of space biology, and in part by emphasizing some relevant aspects of standard theoretical biology. They will permit us to show the mistakes in the two notions that buttressed the general low estimate of the value of space biology.<span> </span>The first notion, we may recall, was that microgravity affects organisms only at the systems level.<span> </span>Investigations then have the main purpose of determining just what systemic effects take place and how they can be corrected.<span> </span>This clinical work has made its practitioners confident that with appropriate compensation (diet, drugs, and exercise) men and women can survive in space for periods of many months, perhaps years.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>But even if this is true, it takes away nothing from the promise of space biology proper.<span> </span>If we wish to determine the role of gravity as an all-pervasive factor in individual development and in patterns of evolution, the systems level is actually not a bad place to begin. The human body, for instance, appears fine-tuned for the Earth's gravity.<span> </span>We might have expected to extrapolate our centrifuge studies here on Earth (with gravities above 1g) to the microgravity of space.<span> </span>Thus if we lose body mass under an acceleration of several g's, have it normal at 1 g, then presumably we would gain mass at less than 1 g. But it turns out that we lose mass at less than 1g. (The body mass in question here is intracellular mass and does not include fluids or calcium loss in the bones, which is itself pronounced and very worrisome.<span> </span>Similar reactions take place in microgravity with temperature control and other physiological functions. The explanation of some of these reactions seems to be that the shift in body fluids that comes from changes in gravity affects the communication between cells.)<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>This fine-tuning of physiology to the Earth's gravity -- which is seldom emphasized if realized at all -- should provide a fruitful theoretical perspective to study the relationships between a variety of internal systems and cycles in the human body.<span> </span>Why are physiological functions maximized at 1 g?<span> </span>This leads to questions about why the body works as it does, questions that would not occur that easily otherwise.<span> </span>A preliminary answer is that gravity is used to harmonize a variety of physiological systems. One way to think about this is that gravity is like the glue that holds such systems together.<span> </span>Once the glue is gone, they do not quite work together.<span> </span>And from their failure we learn what makes them work correctly under terrestrial conditions.<span> </span>Another way to think about it is that those systems change their responses in order to adapt to the new conditions. That may also give us significant clues about their normal modes of interaction with other systems or mechanisms.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>This fine-tuning to 1g may become acute in issues of development.<span> </span>In microgravity a human male excretes from 1.5 to 2 liters of body fluids, with pronounced reductions in the levels of sodium and potassium.<span> </span>By contrast a pregnant human female is expected, in 1g, to show an increase of 1.5 to 4 liters over her pregnancy, with a marked retention of sodium.<span> </span>Since the development of the fetus follows a strict sequence in which each event must take place within a critical period, and since the availability and composition of the body fluids is essential to the proper environment in the placenta, we can readily see that disruptions at the system level affect physiological processes at lower levels.<span> </span>At the present time it would be morally impermissible to have pregnant women in space.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>The human body is resourceful; it may be able to compensate for the effects of microgravity in a systematic fashion even during a pregnancy.<span> </span>But to determine whether it can, we must resort to experiments on animals.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__edn6" name="1308292f03be78dd__ednref6" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[6]</span></span></span></span></a><span> </span>By removing gravity, then, we can observe how the development comes unglued; by "dialing" several degrees of gravity we can refine our examination.<span> </span>The mere fact that many systems function optimally at 1 g provides warrant for designing experiments to determine how the timing and feedback controls of development operate.<span> </span>This, it seems to me, is not a matter of small importance.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>"Mere" systemic effects can have profound repercussions.<span> </span>A clever probing of them can reveal much not only about development but also about the operation of many physiological functions, including their coordination.<span> </span>This possible gain in knowledge may extend to the cellular level, in spite of the experiments on cells mentioned earlier. The cells of complex organisms are parts of cellular systems, for example, of specialized tissue.<span> </span>The role cells play in those systems largely affects how the structural elements of cells operate.<span> </span>Those structural elements (called cytoskeletal) are responsible for communication among cells, transportation of plasmas, and maintenance of the cells' compartments.<span> </span>Changes in the environment of the cell lead to cellular changes in shape, in ability to move, and in internal metabolism (i.e., polarity, secretion, hormone regulation, membrane flow, and energy balance).<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__edn7" name="1308292f03be78dd__ednref7" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[7]</span></span></span></span></a><span> </span>Changes that take place at the systems level in the organism, such as body fluid shifts, are bound to affect several cellular systems, change the cellular environment, and thus affect the cells themselves.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>The experiments that indicated that gravity was irrelevant at the cellular level were performed in cell cultures; they did not examine cells that formed part of the complex wholes that are the cells' normal environments.<span> </span>It is not surprising, then, that such experiments could not expose the indirect action of gravity that starts at the systems level of the organism and works its way down into the realm of the small.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>Since genes contain the “language of life,” and since organisms are presumably the books written in that language, we tend to think that significance in biology goes from the small to the big.<span> </span>But we have just seen that much of the small depends on the big, since the function of the small depends on the larger whole to which it belongs (and that whole often depends on an even larger one of which it is a part, and so on).<span> </span>It is true, however, that genes are in some sense supposed to be independent of the organism's environment: Theory demands that genetic variation not be coupled to the mechanism of selection (i.e. that the environment cannot have a hand in inducing the variations that are compatible with it, otherwise it would be possible to inherit acquired characteristics).<span> </span>Nonetheless, even if this demand is strictly interpreted,<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__edn8" name="1308292f03be78dd__ednref8" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[8]</span></span></span></span></a> many molecular processes may still be open to the influence from above I have just discussed. </span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>It is also true that, in many areas of biology, real and fundamental progress is achieved when a strong connection can finally be made to the genotype of the organism in question; that is, when we can finally explain how the genes give rise to the mechanism or function in question.<span> </span>Be that as it may, it is misleading to think of genes as the blueprint of some sort of archetype that the organism will grow into, barring acts of God and other misfortunes. Given a certain genotype -- and the right circumstances at many different stages of development – a certain individual organism will likely be the outcome.<span> </span>But at many critical junctures within those stages of development, things could go slightly differently. The outcome would be a different organism. </span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>The important point for our issue is that at those critical junctures, genes and the various structures to which they give rise take advantage of many environmental constants in order to keep their appointed rounds. Nature does not create everything anew and at once.<span> </span>It takes advantage of what is already there; it builds on the structures it finds in place; it develops not by reaching for an ideal but by a process best described as jury-rigging.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>My suggestion is, of course, that the fine-tuning of several physiological functions for 1 g indicates that gravity is one of those constants that provide the context in which the language of life comes to make sense. Without it, aspects of the human genotype would be expressed very differently, if they could be expressed at all.<span> </span>If my suggestion is correct, the manipulation of gravity could return a theoretical profit to the study of genetics in space. </span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>The reason becomes clearer if we emphasize some of the points already made.<span> </span>It is not easy to discover genes and then ask what they do.<span> </span>Often the question goes from the top down: given a certain function or structure, how do genes contribute to bring it about?<span> </span>This indicates that we need knowledge of all the other levels in order to guide genetics.<span> </span>Moreover, it is not necessary that all the alignments and states of equilibrium that many physiological systems reach be encoded in any one set of genes.<span> </span>Some genes may have been selected for because they lead to the construction of an organ or function that finds accommodation with earlier organs or functions.<span> </span>And the genes that lead to those earlier organs or functions are now preserved because the new arrangements are advantageous to the organism as a whole.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>The point is this: Even if we knew what genes brought about the newer organ or function, and even if we knew all the steps in the construction, we still would not understand that aspect of physiology.<span> </span>For those genes and those steps make biological sense only against the background of the existence of those other organs or functions.<span> </span>And all these together make sense only in the context of whatever constants a form of life has come to take for granted.<span> </span>Thus, for example, the pattern of a net of nerves may not be encoded in the genes.<span> </span>The only "instruction" may be for the nerves to keep growing in search of a particular chemical attractor, but since the tissue in which they grow does not permit easy penetration, the nerves have to work their way around. (See Figure 10)<span> </span>The result is a very specific kind of net, although nowhere in the genotype could we find the "blueprint" for such a net.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__edn9" name="1308292f03be78dd__ednref9" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[9]</span></span></span></span></a> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>The moral of this story is that knowledge of one level – even if it is "fundamental" – is very limited without knowledge of the other levels.<span> </span>But this more complete knowledge can be gathered only to the extent that we grasp the context in which genes find ultimate expression.<span> </span>And that requires the manipulation of constants in order to determine their role.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__edn10" name="1308292f03be78dd__ednref10" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[10]</span></span></span></span></a></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>I have already suggested some reasons why gravity is one of those relevant constants.<span> </span>It may turn out, of course, that the actual threshold for the proper functioning of physiological and developmental is less than 1g; that as soon as a gravity vector (direction and intensity of gravity) is detected, things will work normally or almost normally.<span> </span>Determining that threshold is one of the important initial tasks of biology in space (that subdivision of the field is called "gravitational biology"), a task that finds no counterpart in doing centrifuge studies on the Earth.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__edn11" name="1308292f03be78dd__ednref11" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[11]</span></span></span></span></a></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>But there are other ways in which genetic studies can be done advantageously in space.<span> </span>In a recent experiment samples of salmonella bacteria flew in the Space Shuttle while control samples under identical conditions, except for the presence of gravity, remained on the ground.<span> </span>The space-traveling salmonella became much more virulent because certain genes changed their level of activity in microgravity – genes crucial to the control of a protein called Hfq, which allows bacteria to adapt to changing conditions<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__edn12" name="1308292f03be78dd__ednref12" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[12]</span></span></span></span></a>. This finding, worthwhile in itself, may also help us understand some causes of increased virulence of such bacteria on Earth.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>It may turn out that we can discover how to compensate for most of the systemic disturbances caused by microgravity in an organism over long periods of time.<span> </span>That would be ideal.<span> </span>We must recall that in many instances proper experimentation requires multi-generational studies, and that multi-generational studies may take years.<span> </span>Not only could we benefit from investigating the effects of microgravity on a variety of organisms, but we could do so without risking serious damage to the biologists carrying out those investigations in space.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>The experimental and theoretical promise of space biology is thus far greater than we may imagine from glancing at a few reports of the rather pedestrian biological experiments that have been done so far. Two further considerations should give solid anchor to this conclusion.<span> </span>The first is conceptual; the second is historical. H.A. Lowenstam and Lynn Margulis have argued convincingly that the ability by eukaryote cells to modulate their internal concentrations of calcium made possible the appearance of calcareous skeletons.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__edn13" name="1308292f03be78dd__ednref13" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[13]</span></span></span></span></a><span> </span>The appearance of such skeletons in turn made possible, over 500 million years ago, the Cambrian Explosion, during which all the major divisions of life became established.<span> </span>The importance of this argument, for our purposes, is that calcium metabolism is one of the first things affected by microgravity.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>Calcium ions in solution are essential for many physiological functions, including cell adhesion, muscle contraction, amoeboid cell movement, and -- as it is now acknowledged -- they are also used to transmit information between cells.<span> </span>Not only is the intracellular regulation of calcium essential to the function of eukaryote cells, it is also important in the genesis of tissues and embryos.<span> </span>The regulation of calcium seems to be one of those physiological functions on which nature has built a whole array of other functions.<span> </span>This key evolutionary role apparently began, according to Lowenstam and Margulis, when "prey, forced to escape from more effective predators, developed highly integrated sensory and motor systems that must have involved increased coordination and speed of the muscle system."<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__edn14" name="1308292f03be78dd__ednref14" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[14]</span></span></span></span></a> These two skills depend on muscle contraction.<span> </span>And muscle contraction "responds directly to calcium release."<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__edn15" name="1308292f03be78dd__ednref15" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[15]</span></span></span></span></a></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>Since the regulation of calcium may have been very instrumental in the evolution of complex organisms, and since life develops in a jury-rigging fashion, the biological importance of calcium may go far beyond what standard theory assigns to it.<span> </span>Determining that importance is precisely one of the areas where experimentation in space can be of advantage.<span> </span>This consideration thus provides one more reason for thinking that in space biology, too, exposure to new circumstances may lead to the profound transformation of our ideas. </span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>The examination of the role of gravity in living things has paid off from the beginning.<span> </span>It was Darwin himself who first noticed that the tips of growing roots and shoots were used to detect gravity.<span> </span>"We now know," he said, "that it is the tip alone which is acted on, and that this part transmits some influence to adjoining parts, causing the latter to bend."<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__edn16" name="1308292f03be78dd__ednref16" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[16]</span></span></span></span></a> The study of this influence, in a long series of experiments beginning with the publication of Darwin's work in 1880, yielded the separation (1920's) and chemical identification (1930's) of the first hormone known to make plants grow.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__edn17" name="1308292f03be78dd__ednref17" title=""><span><span><span><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;">[17]</span></span></span></span></a><span> </span>Space biology proper seeks the opportunity to continue this history.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>Nevertheless, even if these considerations are admitted, the question remains whether the large expenditures of space biology are justified when its significance is more of promise than of record.<span> </span>“$50,000 can pay for a decent experiment in standard biology today,” a biologist told me in the 1980s.<span> </span>But for that money we could hardly get a rabbit into orbit, to say nothing of enough rabbits for biologists to supervise multi-generational studies in space.<span> </span>We must notice, however, that this complaint does not deny that space may be beneficial to biology, or that it may be beneficial in important ways. Its aim is rather to make us favor Earth-based investigations -- which we already know are very important -- over the expensive biological experimentation in space. </span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>Space biologists often respond in two ways.<span> </span>First they point out that their budgets have been small as space budgets go (in the 1980s, for example, it was about $30 million a year -- including the monies for exobiology, gravitational biology, and flight experiments -- which was roughly about 3% of the total space science budget, and not much when compared to all the monies spent for biological research on Earth).<span> </span>Their second point is that most of the money for space biology is not going to come from the general funds earmarked for the life sciences. The money is going to come from space exploration funds.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>Critics are unlikely to accept these two points.<span> </span>First of all, even if the space biology budget is a pittance, to do the research properly would take far greater amounts.<span> </span>For example, if space biology is used as one of the justifications for building the space station, we would have to think in terms of hundreds of millions of dollars.<span> </span>As for the second point, to say that the two are not really in competition for the same monies is an easy out.<span> </span>For whatever the name of the account, in the long run society pays for both.<span> </span>Why should space biology take so large a share?<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; font-family: "Geneva","serif"; color: black;"><span> </span>Nevertheless the matter is not as simple as that.<span> </span>Space biology does indeed belong to a large space commitment. Because of that, the notion of competition between standard biology and space biology flounders. To see why, imagine what happens to a man who buys an automobile and wants a radio in it.<span> </span>For the amount of money that he will have to spend, he could have gotten several radios far superior to the one that goes into his car.<span> </span>But those radios would not do quite the same job effectively.<span> </span>Similarly, since we are going into space we have an opportunity to investigate life in ways not open to us before.<span> </span>The whole question of doing space biology must then be taken in the context of having a space program, just as the question of having the car radio arises in the context of having a car and not in that of purchasing radios generally.<span> </span>All the while we must keep in mind how promising a radio this is.</span></p> <p class="MsoNormal"> </p> <div><br /> <hr align="left" size="1" width="33%"> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__ednref1" name="1308292f03be78dd__edn1" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[1]</span></span></span></span></a> <span style="color: black;">From the "Final Report of the Developmental Biology Working Group," p.3. (Not yet published, extended to me as a courtesy of Dr. Emily Holton).</span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__ednref2" name="1308292f03be78dd__edn2" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[2]</span></span></span></span></a> <span style="color: black;">For a brief summary see G.R.Tylor (Note 19), p.103. For a full report see H.W. Scheld et al, "Killifish Development in Zero-G on COSMOS 782," p.179, NASA TM-78525.<span> </span>Unpublished Soviet studies, however, have raised serious doubts, in J.R. Keefe's opinion, "about the ability of normal vertebrate fertilization under spaceflight conditions." ("Gravity is a Drag," p.6. Unpublished).<span> </span></span></p> </div> <div> <p class="MsoNormal"><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__ednref3" name="1308292f03be78dd__edn3" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[3]</span></span></span></span></a> See the <i>Annals of Botany</i> supplement cited in Note 17. Dr. Holton has made available to me data from Soviet experiments that show very low yields and that suggest that flowering and fertilization may be sensitive to gravity (as indicated, for example, by lost chromosomes in Dwarf Sunflower and broken chromosomes in oats).<span> </span>When cells are studied not in culture but as part of a system, there is a peculiar increase in chromosomal abnormalities in the majority of organisms, including humans.<span> </span>See, for example, L.H. Lockhart, "Cytogenic Studies of Blood (Experiment M111)," <i>Biomedical Results from Skylab</i>, op. cit., p.217.<span> </span>Investigators are much too quick, in my opinion, to explain away such widespread abnormalities as possible effects, exclusively, of flight stresses.<span style="color: black;"></span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__ednref4" name="1308292f03be78dd__edn4" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[4]</span></span></span></span></a> Whether atoms existed at all was a matter of controversy amongst physicists.<span> </span>Ernst Mach, for example, argued that their existence was not a scientific claim.<span> </span>The controversy was settled in 1905 with the publication of Einstein’s work on Brownian motion.</p> </div> <div> <p class="MsoNormal"><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__ednref5" name="1308292f03be78dd__edn5" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[5]</span></span></span></span></a> We might ask whether it is fair to have to spell out the warrant for investigating the role of gravity in biology.<span> </span>After all, the history of science is full of cases where investigations that were considered preposterous led to the most profound changes in thought.<span> </span>But we cannot take this easy way out when space biology requires large sums of money and its critics have credentials and influence.<span> </span>The issue must be faced.<span style="color: black;"></span></p> </div> <div> <p class="MsoNormal"><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__ednref6" name="1308292f03be78dd__edn6" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[6]</span></span></span></span></a> Of particular interest would be animals who exhibit a highly differentiated ability to distribute fluids (e.g., Gerbilline rodents).<span> </span>"Final Report of the Developmental Biology Working Group," op. cit., p.6. <span style="color: black;"></span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__ednref7" name="1308292f03be78dd__edn7" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[7]</span></span></span></span></a> <span style="color: black;">Ibid. p.5.</span></p> </div> <div> <p class="MsoNormal"><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__ednref8" name="1308292f03be78dd__edn8" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[8]</span></span></span></span></a> Every system of the organism tries to maintain homeostasis (a relatively stable state of equilibrium) against the next higher level, and the organism as a whole against the environment.<span> </span>Thus the genes benefit from many levels of homeostasis serving as a buffer zone against the environment.<span> </span>Nonetheless it is clear that the general environment sometimes will affect the intracellular environment and thus may conceivably act as an agent of selection against some pieces of DNA and in favor of others (at the molecular level, that is). This is not to say that acquired characteristics can be passed on, since the features of the environment that will favor some traits at the level of the organism are not of a kind with those that would act on pieces of DNA within the cell.<span> </span>That is what happens, for example, when a change in the cellular environment may permit a mutation to survive which will later be considered a defect of the organism vis. a vis. the general environment. <span style="color: black;"></span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__ednref9" name="1308292f03be78dd__edn9" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[9]</span></span></span></span></a> <span style="color: black;">Stent's work on nerves.</span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__ednref10" name="1308292f03be78dd__edn10" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[10]</span></span></span></span></a> <span style="color: black;">I take it that the general point I am defending here is a corollary of the views I expressed in Chapter 8 of my <i>Radical Knowledge: A Philosophical Inquiry into the Nature and Limits of Science</i>, Hackett, 1981.<span> </span>It is also an expansion of Gunther Stent's work on the "meaning" of the genetic code.</span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__ednref11" name="1308292f03be78dd__edn11" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[11]</span></span></span></span></a> <span style="color: black;">In general, centrifuge studies can be extrapolated to space conditions only with the greatest of cautions.</span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__ednref12" name="1308292f03be78dd__edn12" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[12]</span></span></span></span></a> This example is taken from S. Williams, “Bugs in Space.”<span> </span><i>Science News</i>, 2007, September 29, Vol. 172, p. 197.</p> </div> <div> <p class="MsoNormal"><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__ednref13" name="1308292f03be78dd__edn13" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[13]</span></span></span></span></a> H.A. Lowenstam and Lynn Margulis, "Evolutionary Prerequisites for Early Phanerozoic Calcareous Skeletons," BioSystems, 12, 1980, p.27.<span style="color: black;"></span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__ednref14" name="1308292f03be78dd__edn14" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[14]</span></span></span></span></a> <span style="color: black;">Ibid. p. 36.</span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__ednref15" name="1308292f03be78dd__edn15" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[15]</span></span></span></span></a> <span style="color: black;">Ibid.<span> </span>See also, S.J. Roux, ed., The Regulatory Functions of Calcium and the Potential Role of Calcium in Mediating Gravitational Responses in Cells and Tissues, NASA CP-2286,1983.</span></p> </div> <div> <p class="MsoNormal"><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__ednref16" name="1308292f03be78dd__edn16" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[16]</span></span></span></span></a> C. Darwin, assisted by F. Darwin, The Power of Movement in Plants, John Murray, 1880, p.592.<span style="color: black;"></span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1308292f03be78dd__ednref17" name="1308292f03be78dd__edn17" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[17]</span></span></span></span></a> <span style="color: black;">Adapted from the Dedication to Charles Darwin in the Proceedings of the Sixth Annual Meeting of the IUPS Commission on Gravitational Biology, op. cit.</span></p> </div> </div> </div></div>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-68451849555053293012011-06-05T01:43:00.000-07:002011-06-05T01:44:24.787-07:00TERRESTRIAL LIFE IN SPACE<div id=":9u" class="ii gt"><div id=":9v"> <p class="MsoNormal"><span style="font-size: 12pt; color: black;">Chapter 6J</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;">TERRESTRIAL LIFE IN SPACE</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;">If a man hangs upside down for many hours, blood will rush to his head, his breathing will be impaired, and he will die.<span> </span>To prevent such a fate, evolution has provided us with means for telling which way is up.<span> </span>In mammals this means includes the otoliths of the middle ear, sophisticated muscular-skeletal sensing devices, and the coupling of eyesight in conjunction with all these organs to the brain.<span> </span>This detection of gravity is no less important to a plant, which needs to send its roots into the ground in search of nutrients, and its shoots into the air in search of gases and sunlight. Since in orbit gravity is practically absent, many experts predicted that the perceptual and physiological disorientation would lead to heart trouble, depression, and mental impairment.<span> </span>The severity of these and other disorders would surely make manned space flight impossible. </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>The march of events has confounded all these dire predictions about the fate of humans and other forms of life in space.<span> </span>Nevertheless, space flight does affect living things in a variety of ways.<span> </span>Caution has been called for, and caution has been exercised.<span> </span>The result has been a large body of research -- mostly clinical research --aimed at insuring the safety of astronauts and at establishing the degree to which humans can adapt to the low gravity and high radiation of space.<span> </span>This body of research does not include all the biological investigations carried out in space, but its prominence has led to a distortion of the significance of doing biology in space.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>Some observers have thus concluded that biological research in space makes sense only if we are planning to continue manned space exploration.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__edn1" name="1305e3da4ef26cf9__ednref1" title=""><span><span><span><span style="font-size: 12pt; color: black;">[1]</span></span></span></span></a><span> </span>Of course, they say, we have to know what space does to a human body if our astronauts are going to spend long times in that environment.<span> </span>And if plants and animals are to be an integral part of man's adventure in space, we will have to learn about how they are affected also. In that spirit I could argue as follows.<span> </span>If <i>other </i>space science is worth doing, as I have shown in the previous two and a half chapters, and if a manned space program greatly advances the cause of space science, then such a program is also justified. </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>Settling for this argument, however, keeps us from subjecting space biology to the same scrutiny we have put the other space sciences through, and we would thus tacitly accept the assumption that space biology has little to offer on its own.<span> </span>Now, there are experts, even in biology, who make precisely that assumption, and my immediate task is to examine their reasons.<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>Part of the problem, as I said earlier, is one of image.<span> </span>For instance, NASA has placed great emphasis on vestibular research, for the function of the inner ear is deeply connected with motor and perceptual systems.<span> </span>Since motion sickness is probably the result of vestibular disorientation, research in this area has shown great concern for the welfare and effectiveness of the astronauts.<span> </span>And thus people who want to turn down support for space biology often say that it is just more research on why the astronauts throw up.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__edn2" name="1305e3da4ef26cf9__ednref2" title=""><span><span><span><span style="font-size: 12pt; color: black;">[2]</span></span></span></span></a></span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>But such remarks are neither accurate nor fair.<span> </span>In space we can ask questions about life that are not possible otherwise.<span> </span>In particular we can study the role of gravity in the structure and the development of organisms.<span> </span>In a space station, for example, we may choose at will the amount of gravity to which plants and animals will be exposed.<span> </span>This can be done merely by the use of a centrifuge.<span> </span>When the centrifuge is off, the gravity is close to zero.<span> </span>And, when it is on, it makes the container go in circles, subjecting the object under study to whatever linear acceleration we wish.<span> </span>To a plant or an animal such acceleration is the equivalent of a gravitational force acting on it.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__edn3" name="1305e3da4ef26cf9__ednref3" title=""><span><span><span><span style="font-size: 12pt; color: black;">[3]</span></span></span></span></a> Our main interest lies in the range between 0 and 1g, since there we may want to study not only the perception of gravity but perhaps even the role that gravity has played in evolution.<span> </span>By experimenting in that range we may be able to determine gravitational thresholds of biological importance; that is, we may determine the minimum level at which gravity can be detected and at which it becomes a significant factor in physiological or developmental functions. </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>But are these important questions?<span> </span>Are there any reasons to suspect that gravity will in fact turn out to be a significant biological factor?<span> </span>At first sight there certainly are reasons.<span> </span>Gravity is all-pervasive in our planet; it is not hard to imagine that life took advantage of its presence to favor some avenues of evolution over others.<span> </span>As Galileo noticed as early as 1638, how much an animal weights depends on how well its bones can support it.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__edn4" name="1305e3da4ef26cf9__ednref4" title=""><span><span><span><span style="font-size: 12pt; color: black;">[4]</span></span></span></span></a> Thus the anatomical structure of an animal -- or a plant for that matter -- depends on gravity.<span> </span>In a planet with lower gravity, we may find much taller animals and more symmetrical trees (the symmetry is often broken because slight differences in mass in the branches weigh the tree down in different ways; the more the gravity the more pronounced those differences become in the development of the tree --see Figure 6).<span> </span></span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>Nor is it difficult to imagine that what is true of anatomy may also be true of physiology and other areas of biology.<span> </span>Indeed the absence of gravity (or, rather, being in microgravity) leads to a shifting of body fluids, and such shifts affect the cardiovascular system in humans.<span> </span>As a result we may have an opportunity to study how the functioning of the cardiovascular system -- or rather its malfunctioning -- is connected with the deterioration of muscles.<span> </span>This of course is a matter of potential significance for the general population, especially for the elderly.<span> </span>Moreover, in microgravity we no longer need many of our big muscles to support us.<span> </span>As a consequence the body begins to reduce its levels of calcium and other minerals needed to strengthen the muscles. This presents a big problem for astronauts, whose bones become weak and brittle. On the other hand, their problem may give us a chance to study the connections between bone and mineral metabolism and endocrine action. Here the adverse reactions of astronauts to weightlessness resemble the symptoms of some diseases on Earth.<span> </span>Space physiology thus offers a chance to investigate the underlying mechanisms of such diseases.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__edn5" name="1305e3da4ef26cf9__ednref5" title=""><span><span><span><span style="font-size: 12pt; color: black;">[5]</span></span></span></span></a> Similar consequences may be derived from the much belittled vestibular research (for example, the study of Meniere's disease, an affliction of the middle ear characterized by deafness and vertigo).</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>By all appearances, then, space biology proper illustrates once more that exposing our ideas to unusual circumstances leads to their transformation, and that the transformed ideas lead in turn to new kinds of practical applications.<span> </span>Furthermore, the possible transformation of our ideas is not limited to physiology, as the following examples indicate.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>The kind of examination made possible by controlled, variable gravity is of fundamental importance in botany.<span> </span>As I mentioned earlier, the perception of gravity directs the way a plant grows. Reaction to sunlight may have been suspected as the main factor some time ago--but no more.<span> </span>For in the microgravity of space roots grow out of the ground into the air and the shoots are generally disoriented in spite of the constant illumination from the top.<span> </span>Gravity is obviously the main factor in the case of the roots; shoots require both gravity and illumination. But how do plants recognize gravity?<span> </span>They have gravity receptors, and thanks to space research we are beginning to understand what those receptors are.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__edn6" name="1305e3da4ef26cf9__ednref6" title=""><span><span><span><span style="font-size: 12pt; color: black;">[6]</span></span></span></span></a> </span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>This possible contribution of space to a seemingly fundamental issue in botany may lead to similar contributions to other branches of biology. It is also interesting, for example, to investigate the ways in which different animals detect gravity.<span> </span>Embriology, the study of individual development, may also benefit from experimentation in space. So far there are indications that gravity may play a role in the axial orientation of amphibian embryos (which is a factor in the normal development of amphibians) and perhaps also in that of birds.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__edn7" name="1305e3da4ef26cf9__ednref7" title=""><span><span><span><span style="font-size: 12pt; color: black;">[7]</span></span></span></span></a></span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>Nevertheless the importance of space biology proper continues to be discounted. It is clear to all parties concerned that judgements of the value of space biology proper should be made relative to what could be accomplished if the money, talent, and effort were directed elsewhere in biology.<span> </span>And the general feeling is that we could do much better.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>This feeling goes hand in hand with the general perception that the biological research done in space is not of very high quality.<span> </span>Such a low evaluation is reinforced by two further notions.<span> </span>The first notion is that all the abnormal effects of gravity take place at the systems level, not at the level of cells.<span> </span>Thus, for example, since we do not need strong bones for support, we lose calcium; this loss may in turn have unusual effects on several physiological functions, and so on.<span> </span>But with appropriate exercise and diet we may preserve our need for strong bones; therefore the system imbalance will be largely corrected and the unusual circumstances will be kept to a minimum.<span> </span>As a consequence, the biological significance of space will also be kept to a minimum.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__edn8" name="1305e3da4ef26cf9__ednref8" title=""><span><span><span><span style="font-size: 12pt; color: black;">[8]</span></span></span></span></a></span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>The correctness of this notion is presumably buttressed by experimental and theoretical considerations.<span> </span>Most space biologists themselves have interpreted the results of many cellular experiments as indications that cells are largely unaffected by gravity.<a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__edn9" name="1305e3da4ef26cf9__ednref9" title=""><span><span><span><span style="font-size: 12pt; color: black;">[9]</span></span></span></span></a><span> </span>And this conclusion comes as no surprise, since it accords with what theory has led them to expect: Cells are small enough that the force of gravity means little when compared to the electromagnetic forces so crucial to the chemical bonds of life.</span></p> <p><span><span> </span>At the molecular level gravity should be even less significant.<span> </span>And this brings us to the second notion at play.<span> </span>Many biologists are inclined to believe that what really matters in biology takes place at the molecular level or close to it; therefore, as far as they can tell, controlling gravity as a factor is not going to bring us great breakthroughs.</span></p> <p class="MsoNormal"><span style="font-size: 12pt; color: black;"><span> </span>I think that the general feeling against the value of space biology proper is misguided.<span> </span>To see why, it is necessary to show why the concerns just expressed are mistaken.<span> </span>I will take them up in order.<span> </span></span></p> <p class="MsoNormal"> </p> <div><br /> <hr align="left" size="1" width="33%"> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__ednref1" name="1305e3da4ef26cf9__edn1" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[1]</span></span></span></span></a> <span style="color: black;">This emphasis is exemplified by the attitude of the National Academy of Sciences.<span> </span>In a report entitled "Space Station Needs and Characteristics," (May 1983) The Committee on Space Biology and Medicine of the Academy's Space Science Board said, "...the main scientific justification for a Space Station Biomedical Laboratory is laying the physiological groundwork necessary for launching manned space flights of long duration sometime in the next century… Although [the zero-g] environment would provide also an opportunity for carrying out some fundamental biological research, we do not believe that this aspect can be a major consideration in justifying the Station." (p.4) The fundamental biological problems recognized by the academy are the perception of the gravitational vector by plants and the determination of body axes in metazoan development (chiefly in amphibians and birds--both problems are discussed in this chapter).<span> </span>It seems that just two problems are not enough, or perhaps these two are not fundamental enough, in the eyes of the academy.<span> </span></span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__ednref2" name="1305e3da4ef26cf9__edn2" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[2]</span></span></span></span></a> <span style="color: black;">Scientists who oppose manned exploration on the grounds that it detracts from real space science often concentrate their fire on space biology.<span> </span>Writing in Nature, R. Jastrow said that the Space Station would be a tragedy, "...another two decades of original research on why astronauts vomit." (Quoted in<u> </u><i>Science Digest</i><u>, </u>May 1984, p.142).</span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__ednref3" name="1305e3da4ef26cf9__edn3" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[3]</span></span></span></span></a> <span style="color: black;">The main difference is that coriolis forces may be more pronounced in centrifuges.</span></p> </div> <div> <p class="MsoNormal"><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__ednref4" name="1305e3da4ef26cf9__edn4" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[4]</span></span></span></span></a> A good source for the state-of-the-art research on how gravity affects life can be found in the proceedings of the annual meetings of the IUPS Commission on Gravitational Physiology, published as supplements to <i>The Physiologist</i>.<span> </span>See particularly Vol. 25, No. 6, Dec, 1982, and Vol. 27, No. 6, 1984. For biology in the Space Shuttle see the series of reports from Spacelab entitled "Life Sciences," <i>Science</i>, 13 July 1984, Vol.225, pp.205-234. For possible future experimentation see <i>The Fabricant Report on Life Sciences Experiments for a Space Station</i>, J.D. Fabricant, ed., a publication of the University of Texas Medical Branch, Galveston, Texas, 1983.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__ednref5" name="1305e3da4ef26cf9__edn5" title=""><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";"><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif"; color: black;">[5]</span></span></span></span></span></a><span style="font-size: 10pt; font-family: "Times New Roman","serif";"> Paul C. Rambout, "The Human Element,: in <i>A Meeting with the Universe:<span> </span>Science Discoveries from the Space Program</i>.<span> </span>NASA (1981), p. 142.<span> </span>In renal and electrolyte physiology also, space brings about many interesting variations from normal.</span></p> </div> <div> <p class="MsoNormal"><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__ednref6" name="1305e3da4ef26cf9__edn6" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[6]</span></span></span></span></a> See the gravitational physiology supplements to <i>The Physiologist</i> cited above.<span> </span>Also see Experiments on Plants Grown in Space, Supplement 3 to Annals of Botany, Vol. 54, (Nov., 1984). For an assesment and long range planning of plant gravitational research see "Plant Gravitational and Space Research," Report of a Workshop held<u> </u>April 30-May 2, 1984 in Rosslyn, Virginia, a Publication of the American Society of Plant Physiology, 1984.<span style="color: black;"></span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__ednref7" name="1305e3da4ef26cf9__edn7" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[7]</span></span></span></span></a> <span style="color: black;">See, for example, S. Kochav and H. Eyal-Giladi, "Bilateral Symmetry in Chick Embryo Determination by Gravity," Science, Vol.171, 1971, p. 1027; and A.W. Neff and G.M. Malacinski, "Reversal of Early Pattern Formation in Inverted Amphibian Eggs," in the Proceedings of the Fourth Annual Meeting of the IUPS Commission on Gravitational Physiology, op. cit., p.119.</span></p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__ednref8" name="1305e3da4ef26cf9__edn8" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[8]</span></span></span></span></a> Although similar research could still be carried out on animals.</p> </div> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1305e3da4ef26cf9__ednref9" name="1305e3da4ef26cf9__edn9" title=""><span><span><span><span style="font-size: 10pt; font-family: "Times New Roman","serif";">[9]</span></span></span></span></a> <span style="color: black;">For this general conclusion about<span> </span>the space environment, see G.R. Taylor, "Cell Biology Experiments Conducted in Space," BioScience, Vol.27, p.102. For an influential experiment on cultures of embryonic lung cells, see P. O'B. Montgomery Jr., et al, "The Response of Single Human Cells to Zero-Gravity,"in R.S. Johnston and L.F. Dietlin, eds., Biomedical Results from Skylab, NASA SP-377, 1977, p.221.</span></p> </div> </div> </div></div>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0tag:blogger.com,1999:blog-5232161716029893381.post-3795410788442247822011-05-28T23:53:00.000-07:002011-05-28T23:54:39.318-07:00The Value of Panspermia<div id=":64" class="ii gt"><div id=":65"> <p class="MsoNormal">Chapter 6I</p> <p class="MsoNormal">The Value of Panspermia</p> <p class="MsoNormal">We have seen that Hoover’s claim to have found fossils of extraterrestrial cyanobacteria in meteorites does not really show that terrestrial life did not originate in our own planet.<span> </span>Even if those structures are indeed extraterrestrial fossils, such an admittedly extraordinary finding would only support the view that alien life has existed.<span> </span>The reasons are simple:</p> <p><span><span>1.<span style="font-family: "Times New Roman"; font-style: normal; font-variant: normal; font-weight: normal; font-size: 7pt; line-height: normal; font-size-adjust: none; font-stretch: normal;"> </span></span></span><span dir="LTR"></span>Fossils are dead things.<span> </span>Those meteorites did not bring living things to this planet.</p> <p><span><span>2.<span style="font-family: "Times New Roman"; font-style: normal; font-variant: normal; font-weight: normal; font-size: 7pt; line-height: normal; font-size-adjust: none; font-stretch: normal;"> </span></span></span><span dir="LTR"></span>Even if they had brought living things to this planet, and no one suggests they did, Hoover went to pains to argue that those structures were too different from terrestrial life, so they had to be extraterrestrial (e.g. only 8 amino acids in common out of 20, although for some reason some of the comments in the <i>Journal of Cosmology</i> referred to 8 out of 22).<span> </span>That is, Hoover gives no evidence that terrestrial life came from elsewhere.</p> <p class="MsoNormal">We have also seen that the value of panspermia as an explanation for the origin of terrestrial life is quite low.</p> <p><span><span>1.<span style="font-family: "Times New Roman"; font-style: normal; font-variant: normal; font-weight: normal; font-size: 7pt; line-height: normal; font-size-adjust: none; font-stretch: normal;"> </span></span></span><span dir="LTR"></span>The motivation for the “impossibility proofs” against the idea that life could originate on Earth is often based on misunderstandings of biology, either of evolutionary biology, or genetics, or both.</p> <p><span><span>2.<span style="font-family: "Times New Roman"; font-style: normal; font-variant: normal; font-weight: normal; font-size: 7pt; line-height: normal; font-size-adjust: none; font-stretch: normal;"> </span></span></span><span dir="LTR"></span>By pointing to panspermia we have not explained the conditions under which life originate at all.<span> </span>That is, by saying that life must have started somewhere else we still have not explained the origins of life.</p> <p><span><span>3.<span style="font-family: "Times New Roman"; font-style: normal; font-variant: normal; font-weight: normal; font-size: 7pt; line-height: normal; font-size-adjust: none; font-stretch: normal;"> </span></span></span><span dir="LTR"></span>When this problem has been addressed by the advocates of panspermia, they have ultimately grounded their views on absurdities, either non-scientific fictions (e.g. Hoyle’s “superior beings”) or patently false claims (e.g. Klyce’s notion that life has always existed).</p> <p class="MsoNormal">This is not to say that the idea of panspermia should not be entertained at all.<span> </span>We do not know yet how life originated.<span> </span>By elaborating different scenarios we challenge our imagination and our understanding.<span> </span>And we prepare ourselves for the fruitful exploration of other worlds where life might exist, or at least might have existed.<span> </span>Having trained our biological thinking on a variety of scenarios, for example, we will be better able to deal with the surprises such exploration is likely to offer.</p> <p class="MsoNormal">Even the idea that living things might hitch rides inside meteorites or comets is not completely implausible.<span> </span>Spores can survive for long times.<span> </span>Extremophiles can withstand, it seems, extreme temperatures or radiation, and in addition to bacteria and lichens, even a very small animal, the Tardigrade, has been shown to survive in the vacuum of space! <a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1303a7f53439f27c__edn1" name="1303a7f53439f27c__ednref1" title=""><span><span><span><span style="font-size: 11pt; line-height: 115%;">[1]</span></span></span></span></a><span> </span>Of course, as we have also seen in this blog, that life can survive in extreme conditions does not imply that life can originate in those extreme conditions.<span> </span>Nor should we infer either that those extreme conditions may persist for millions, let alone billions of years, as the interstellar journeys envisioned by some panspermia advocates would require, without destroying the extremophile voyagers.</p> <p class="MsoNormal">A plurality of views may also help us determine what new types of observations and experimental investigations might be worth undertaking.<span> </span>All in all, the idea of panspermia might still prove useful as we search for life in the universe.</p> <div><br /> <hr align="left" size="1" width="33%"> <div> <p><a href="https://mail.google.com/mail/?ui=2&view=bsp&ver=ohhl4rw8mbn4#1303a7f53439f27c__ednref1" name="1303a7f53439f27c__edn1" title=""><span><span><span><span style="font-size: 10pt; line-height: 115%;">[1]</span></span></span></span></a><span>Jönsson, K. Ingemar; Rabbow, Elke; Schill, Ralph O.; Harms-Ringdahl, Mats; Rettberg, Petra (2008-09-09). "Tardigrades survive exposure to space in low Earth orbit". <i><a href="http://en.wikipedia.org/wiki/Current_Biology" title="Current Biology" target="_blank">Current Biology</a></i> <b>18</b> (17): R729–R731.</span></p> </div> </div> </div></div>Gonzalo Munevarhttp://www.blogger.com/profile/01949177947376556129noreply@blogger.com0