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Saturday, March 27, 2010

Space Technology and Economic Expansion

The Dimming of Starlight

Chapter 2E

Space Technology and Economic Expansion

One of the most important aspects of space exploration, according to its supporters, is that the drive into space drives technology as well. This should be expected, they say, since in order to meet new challenges and solve new problems, we have to stretch our ingenuity well beyond the bounds of the ordinary. The result is beneficial because many of these advances in technology can be applied here on Earth. That is, from the space program we derive valuable “spinoffs.” These come mainly in two categories. Some technological innovations are entirely extensions or applications of technology developed for space. And some others are developed independently of the space program but become well known, refined, or simply marketable because their use in the space program gives them a great boost.

The effectiveness of space technology in producing spinoffs cannot be determined precisely. One reason is that highly specialized technology may take a long time, often decades, getting to the marketplace. Penicillin and television, for example, were ignored for years before somebody decided to take advantage of them. Nevertheless there appear to be direct links to the technology of space (particularly in the 1960s) in the development of new materials and techniques for aerodynamics, propulsion, electronics, and other fields. The developments in turn affected our systems of transportation, transmission of energy, and temperature control.

Even esoteric space technology often finds a home in the wider industrial world. The liquid hydrogen used as fuel in the Saturn V (the rocket that took men to the moon) had to be kept at the incredibly cold temperature of minus 423 degrees Fahrenheit. The fuel-tank insulation, which consisted of a one-inch thickness of polyurethane foam reinforced in three dimensions with fiberglass threads, is now applied in ships that transport liquefied natural gas. The conversion of the gas to liquid reduces its volume more than 600 times, which makes it a far more economical and manageable cargo. But liquefied natural gas must be contained at about minus 260 degrees Fahrenheit to prevent loss by boil-off, a task Moon technology has made safer and more efficient. Indeed there are many applications of insulating materials designed for NASA. One such spinoff, Therm-O-Trol, provided the insulation required to keep the oil in the Alaska pipeline flowing at 180 degrees Fahrenheit. And Nunsun, a thin film of reflective insulation developed to protect spacecraft from intense solar radiation, can now be sprayed on the windows of buildings to reduce the cost of cooling.

Examples of applications and their influence in industry and daily life multiply easily.[1] In the first two decades of exploration, space supporters pointed to that influence, whether direct or indirect, in thousands of products, from fire-fighting equipment and freeze-dried foods to hand-held calculators and digital watches. Indeed, the whole trend towards miniaturization, it is said, was spurred largely by the technical needs of the space program.[2]

Today, of course, the list of products, and of the fields in which we can find them, is much longer. Here is a small sample of applications and their origins in the space program.

In health and medicine:

Non-surgical breast biopsy system (Space telescope technology: digital imaging)

Ocular screening (NASA Image Processing), a photo-refractor that analyzes retinal reflexes

Ultrasound skin damage assessment (NASA ultrasound technology)

Voice-controlled wheelchair (NASA teleoperator and robot technology)

Programmable Pacemaker (NASA computer technology)

In public safety:

Emergency response robot used in hazardous duties (NASA robotics)

Pen-sized personal alarm system (space telemetry technology)

Self-righting life raft (Apollo program)

In transportation:

Advanced lubricants for railroad tracks, prevention of corrosion in electric plants, etc. (Space Shuttle Mobile Launcher Platform)

Flywheel energy storage system, with 50 times more capacity than a standard car battery (NASA sponsored studies)

Studless winter tires (made from Viking Lander parachute materials)

Improved aircraft wing and engine designs (from multiple NASA technologies)

These are examples chosen almost at random from among many thousands. One could compile similar lists of applications in other fields. Manufacturing, for example, benefits from NASA developments in magnetic liquids, new welding technology, and microlasers. An interesting spin-off is a system of magnetic bearings that allows motion of parts without friction or wear. This technology came from the Space Shuttle and is used for refining oil, building natural gas pipelines and operating machine tools.

I have mentioned the origins of these spinoffs because the popular literature is full of questionable examples and some of the claims about the extent of space technology's influence on the development of specific products are disputed from time to time. Among the most notorious cases are Teflon, Velcro, ballpoint pens and cardiac pacemakers. Carl Sagan recalls meeting the inventor of the cardiac pacemaker, “Who himself nearly had a coronary accident describing the injustice of what he perceived as NASA taking credit for his device.”[3]

Nonetheless, it seems that, as we saw above, space technology has improved considerably the quality of life for many people: here by saving it; there by making it more bearable;[4] elsewhere by creating copious new opportunities in jobs and industries, or innovative products that enhance our work and our leisure. The enthusiasts suggest that much of this change is for the better, and that when people acknowledge the pervasive role of space exploration in their lives, they will realize that they cannot do without it.[5]

[1]. Literature describing actual and possible applications of space technology is easily available at any bookstore. Apart from this popular literature, the reader may wish to consult NASA's periodic summaries, appropriately entitled Spinoff (many of the examples given in this chapter are taken from Spinoff 1979 and Spinoff 1984). Of almost historical interest in the forecasting of the industrial benefits of space exploration is Neil P. Ruzic's The Case for Going to the Moon, Putnam's Sons, 1965.

[2]. Although, as Jerome Schnee points out, the contributions of defense R&D were also very large. See his "The Economic Impacts of the U.S. Space Program," in T. Stephen Cheston, Charles M. Chafer, and Sallie Birket Chafer, Social Sciences and Space Exploration, NASA EP-192, 1984, p. 24.

[3]. Carl Sagan, Pale Blue Dot: A Vision of the Human Future in Space, Random House, 1994, p. 272.

[4] For medical advances produced by the early exploration of space see T.E. Bell, “Technologies for the Handicapped and the Aged,” NASA Technology Transfer Division, 1979, a report for the Select Committee on Aging and the Committee on Science and Technology, U.S. House of Representatives.

[5] For an account of the accomplishments of the American space program during its golden age, see F.W. Anderson, Jr., Orders of Magnitude: A History of NACA and NASA, 1915-1976, National Aeronautics and Space Administration, 1976.

Saturday, March 13, 2010

The Standard Case for Exploration


CH. 2d


The supporters of space exploration do not feel overwhelmed by the challenge. They believe their case is straightforward: space exploration can contribute greatly to the reduction of human misery, the improvement of human life, and the preservation of the environment. In fact, it already has. To appreciate the actual and potential contributions of space, we need only pay attention to the function of satellites, the indirect consequences of space technology (spinoffs), and the opportunities that future exploration may create for humankind. And once we gain an appreciation of these contributions, we will have an answer to the social and ideological critics.


Weather satellites have extended the range and accuracy of weather forecasts appreciably. The reason is simple: from space we see weather patterns that otherwise could be discerned only with great difficulty and never very accurately. Now we see them and track them.[1] Weather satellites warn us about freezes, hurricanes and tornados, thereby saving crops, buildings, and human lives.[2] And when disaster nonetheless strikes, communication satellites enable us to come to the assistance of those in peril or in need of relief.

Apart from this reduction in human misery, the drastic improvement in weather forecasting techniques is of great help to farmers in planting and harvesting, with obvious beneficial consequences for agriculture and the food supply of a hungry world.

Land satellites (LANDSATs and their descendants) are a useful complement to weather satellites. LANDSATs survey the Earth's resources from space, identifying minerals or types of vegetation by their responses to infrared, visible, or ultraviolet radiation. Often, a computer assigns contrasting colors (e.g., gold and purple) to slightly different frequencies (e.g., the frequencies of two closely related browns) that reflect from different materials (e.g., a mineral ore and dry vegetation). This use of “false color” and other computer tricks of remote sensing permit practically instant visualizations of the distribution of natural resources.

We can observe these patterns even on cloudy days, for we can take pictures at wavelengths of the electromagnetic spectrum not absorbed by water droplets. So we can reliably use LANDSATS to look for oil and other mineral deposits; make crop inventories; and carry out surveys of ice in lakes and of snow accumulation on mountains, thus helping to determine the likelihood of flooding. We can also measure the availability of water where it depends on snow melt; estimate forest land; and determine the degree to which urban sprawl affects the surrounding environment. And finally, although the list could go on, we can often monitor the spread of pollution.

Since we can make estimates of the distribution of many resources, and of the productivity of many enterprises, we can see how space technology may be of great assistance in the fight against poverty. Remote sensing technology may also enable us to perform the inventories needed for the preservation of agriculture, wild lands, and wildlife. It seems then that land, weather, and communication satellites begin to answer the concerns of the social and ideological critics of space exploration (see Figures 2.1 and 2.2).

We must recall also the revolution in communications made possible by satellites. We now transmit information and contact people in ways that were unattainable prior to the launching of Sputnik I in 1957. Today, in the comfort of our living rooms, we can watch live on television a sporting or cultural event that is taking place on another continent, or have a telephone conversation with a friend at the opposite side of the world. The significance of these changes becomes evident when an emergency prompts our call to the other side of the world, or when the satellites are used, as in India, to bring education to large rural areas for the first time. And do not forget that the global Internet would not be possible without communication satellites. All these changes in people's daily lives are mirrored by improvements in the practice of commerce, the gathering of news, and the relief of disaster.

The Space Shuttle, as well as other piloted vehicles and the various kinds of space stations, complement these functions of satellites. A 1994 Space Shuttle flight yielded preliminary radar measurements of hitherto undiscovered structures around Angkor Wat, a famous archeological site in Cambodia. NASA’s Jet Propulsion Laboratory then developed a sophisticated airborne radar system that allowed archeologist Elizabeth Moore and her team to discover four to six more temples and gain a better picture of the massive waterworks that were an integral part of the complex.[3]

Few of these accomplishments were likely through more conventional methods. Surveys from the ground could not compete with a perspective that permitted us to detect, at a glance, large patterns and to take inventories of minerals and vegetation. It might be imagined that perhaps airplanes could have flown high above the clouds to do a similar job for less money. But whereas satellites give us pictures of exactly the same spot time and again so we can make comparisons, the flight path of airplanes is never that precise. Nor are airplanes as reliable – they are subject to mechanical problems and the vagaries of weather. Moreover, it would have taken a fleet of thousands of airplanes to do what a single satellite does in passing over the Earth at its very high orbital speed. Using airplanes might have well cost us hundreds of times more and the results would have been vastly inferior.[4] Today we are beginning to use new generations of light planes and other flying devices to obtain more specific local information, normally interpreted in the larger context provided by satellite data.

In any event, many crucial jobs can be done only from space. For a variety of reasons, many weather and communication satellites must be placed exactly over the same spot on the Earth. For example, a satellite fixed overhead is extremely convenient, since we can then transmit and receive from it at any time. As the Earth rotates, the satellite must rotate with it so as never to lag or move ahead. Only a special orbit, called a geosynchronous orbit, 36,000 Km. (22,000 miles) over the equator satisfies these requirements.

Of course, this is only the beginning. New generations of satellites will do far more. Future LANDSATs, for instance, may be helpful in estimating agricultural yields (which would be an important refinement over the presently available crop estimates), once we have a better knowledge of the connections between cloudiness, rainfall, and soil moisture. Merely two decades ago, the very idea of cellular telephones, to say nothing of tracking devices for trucks and mountain climbers, had an aura of science fiction. Now we can expect that future SEASATs and navigation satellites will not only survey the oceans, but also contribute to the safety of travelers and cargo.[v] All in all, new kinds of satellites will improve in new ways the lives of billions and billions of human beings.

[1]. Until 1980 weather satellites led to significant improvements in weather predictions mostly in the southern hemisphere and over the oceans, not in the advanced, populated areas of the northern hemisphere. The reason is that temperature and pressure at different altitudes could be better determined by other technological means. And improvement in the computer weather programs in 1980 led to new and more powerful forecasting techniques in which satellites played a crucial role. Future generations of weather satellites will provide more refined measurements.

[2] The number of hurricane casualties shows a steady decline. In the 1900 Galveston Hurricane, for example, about 8,000 people died. Death tolls around 1,000 resulted from hurricanes in 1919 and 1926. It was not uncommon to see even higher casualties in the first part of the 20th Century. By the 1960s and 70s, the numbers were more typically in the low hundreds. Today they are in the dozens.

The one disastrous exception is hurricane Katrina, which may have caused close to a thousand deaths in Louisiana, Mississippi, and Alabama. Here we have a case, however, in which the warning was delivered but not properly heeded. In many cases, it seems, the reduction of casualties over the last two decades made some people overconfident, and many refused to leave the area. To make matters worse, the evacuation plan for the city of New Orleans was not followed, even though a run-through a year earlier showed that more than 100,000 people were likely to stay in the city unless city and school buses (and probably additional transportation from the state of Louisiana) were pressed into service. For over twenty years it was known that a hurricane that strong would destroy the levees and flood the city. But no one took steps to prevent the calamity. A tragedy of errors turned a serious but still manageable problem into probably the worst natural disaster in the history of the country. One shudders at the thought of what would have happened without the satellite warnings. Incidentally, military and civilian satellites, including Ikonos, a private imaging satellite operated by Space Imaging, are already giving us a reliable assessment of the damage.

[3]. Science News, Vol. 153, February 21, 1998, p. 117.

[4]. For details see The Impact of Space Science on Mankind, op. cit., p. 82. For a summary of the benefits derived from Landsats and environmental satellites, see the same work, pp. 67- 111. In it there are also discussions of communication and weather satellites.

5. Satellites may also be used to survey the resources of the oceans and to carry out sophisticated measurements of temperature and height of the ocean waters.

Saturday, March 6, 2010

Social Critics of Space Exploration

The Dimming of Starlight

Chapter 2c

Social Criticisms of Space Exploration

The typical social critics oppose space exploration on what we may call humanitarian grounds. They cannot justify spending billions of dollars to find out what the Moon is made of at a time when hunger and poverty are rampant on our own planet. As they see it, space exploration takes money, resources, and talent away from helping people in need and from improving the quality of life for everybody. The human condition, one might quip, ought to take precedence over the condition of alien atmospheres and surfaces.

Unlike their ideological counterparts, some of these social critics may even think that space exploration is a good thing. They may agree that producing knowledge and satisfying man's intellectual curiosity and thirst for adventure are all worthwhile goals. But they may also think that opera is a good thing without being prepared to spend billions of dollars in its support. The problem is not what space exploration tries to accomplish but rather the commitment of resources upon which other human needs may have a larger claim.

Now, when we speak of improving the human condition and satisfying other human needs, it is important to be specific. Presumably there are areas of human suffering that come starkly to mind and demand immediate attention. Indeed there are: Millions, perhaps billions, of people in the world suffer hunger and malnutrition, lack proper housing, education and opportunity, and are afflicted by myriad diseases. But even this list does not convey the full extent of misery. To do so, we must attempt to understand the hopelessness, the sense of being at the whim of tragedy – a tragedy brought about by nature, by man, or by man's indifference. These are the burdens we should lift from the people of the Earth before we go looking under the rocks of far-away worlds.

The two categories of criticism – social and ideological – are by no means clear-cut. Many critics would combine them or deviate in important respects from both. Still other critics may oppose space exploration on the prosaic grounds that it is not cost-effective.[1] Nevertheless, I think that my presentation of the main objections captures the essential challenge to the supporters of space exploration. Those supporters will, therefore, have to show, first, that in exploring the cosmos humankind is pursuing goals (or satisfying inclinations) that are in themselves worthwhile. And second, that such pursuit does not proceed at the expense of even more worthwhile goals.