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Saturday, October 8, 2011




One of Rousseau's complaints against the arts and the sciences was that they weaken the military might of a society. "All examples teach us," he said, "that in military 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. Today those who share Rousseau's suspicion of science do so for different reasons. He worried that science made us if anything less formidable. They worry that it makes us far too formidable.

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). The objection is rather that space technology puts into the hands of man tools that he cannot fail to mishandle. 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. Is it not true that rockets have been used to kill and terrorize in the past? 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? Are they not still a great threat today?

The point is not merely that there is a connection between space and grief. The point is rather that the connection is somehow unavoidable, that you cannot have one without the other. 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.

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. But this line of argument operates in a rhetorical vacuum. 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. And how are those reasons going to be assessed? On their merits, one might hope. But what are their merits? What makes causal and probable connections plausible in the first place? I submit that these difficult matters are most often influenced by the way we have learned to judge. And what has determined that learning if not our perception of how similar matters have been resolved? We appeal, that is, to our experience, and in the last analysis, to history. 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.

The wish to explore beyond the confines of our own world is very old. By 180 AD it received full treatment in Lukian's Vera Historia (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 Sleep, a novel about a trip to the Moon. 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. 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. In Germany there was Ganswindt, who worked on a hopeless steam jet to propel his spacecraft. And everywhere there were fiction writers taking their readers on trips that engineering could not yet make available.

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. 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. And the problem was that, to many “experts” at the time, space flight seemed not merely far fetched but physically impossible. Some disheartening calculations, for example, showed that however efficient the production of thrust, no rocket could raise its own mass into orbit. 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. The first stage gives the whole rocket an initial boost and then separates. At that point a second stage takes over the task of pushing a lighter vehicle with a now shorter distance to climb. One or two more pushes like that and the rocket achieves orbital velocity.

A second barrier was overcome by the switch from solid to liquid fuels. Standard rockets generally used solid fuels, mostly gun powder, which lacked both the power and the control required for space flight. 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. This is of particular importance to our question, as we shall see. 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 The Spaceflight Revolution, from which most of the following account is taken). 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. 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.

In the second important respect, control, the differences are just as pronounced. The difficulty with a solid propellant is that it tends to burn until it is exhausted. You cannot just shut it off and start it again. 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. 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. 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.

The three pioneers also provided basic formulas for engine performance and specified likely vehicle trajectories. Now the goals were clarified, and so were the means for attaining them. Nevertheless, the move toward space did not quicken its pace for a long time. 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. But most technically qualified people regarded the topic with suspicion and did not bother themselves with an investigation of it. There is nothing conspiratorial or shortsighted in that attitude. Any scientist may well be bombarded with a myriad of ideas that he himself has not examined in detail. Which ones should he explore? Not all of them. He cannot. And surely not those that strike him as implausible or without foundation. Time is too short for that. 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. Most beginnings are therefore small, and the development of space technology was no exception.

The dreams of the pioneers were left for others to realize. Tsiolkovsky remained undiscovered and ignored. Goddard was very secretive about his own work. 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. Complete reports of his experiments in the 1930s were not published until 1961, the year that Yuri Gagarin orbited the Earth." This situation was apparently more the result of his peculiar temperament than anything else. 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. He seemed to want to achieve successes...then burst upon the world in triumph." But one man alone could not achieve what took the efforts of many thousands. Such were the first quirky steps in the strange journey that took us to the Moon.

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. 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. 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."

Oberth presented his masterwork The Rocket into Interplanetary Space as his doctoral dissertation in 1922 (Goddard's crucial theoretical work preceded his by ten years, and Tsiolkovsky's by twenty). He was turned down with the advice to look for a more suitable topic. He refused, and then proclaimed that he could become a greater scientist than his examiners, "even without the title of doctor." His arrogance was not entirely misplaced. 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." In any event, it became not only a source of inspiration but also the textbook for the German rocket experimenters. One such group, founded in 1927, the VFR--Verein fur Raumschiffahrt (Society for Space Travel) -- was to prove of crucial importance.

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