Broca's Brain - Carl Sagan [124]
On January 2, 1902, we know from Goddard’s notebook, he wrote an essay on “The Habitability of Other Worlds.” The paper had not been found among Goddard’s writings, which seemed to me a great pity, since it might have given us a better understanding of the extent to which the search for extraterrestrial life was a prime motive in Goddard’s lifework.*
In his early postdoctoral years Goddard successfully pursued an experimental verification of his ideas on solid- and liquid-fueled rocket flight. In this endeavor he was supported principally by two men: Charles Greeley Abbott and George Ellery Hale. Abbott was then a young scientist at the Smithsonian Institution, of which he later became secretary, the quaint designation by which the executive officer of that organization is still known. Hale was the driving force behind American observational astronomy at the time; before he died he had founded the Yerkes, Mount Wilson and Mount Palomar observatories, each housing, in its time, the largest telescope in the world.
Both Abbott and Hale were solar physicists, and it seems clear that both had been captured by the young Goddard’s vision of a rocket sailing free above the obscuring blanket of the Earth’s atmosphere, able to view the Sun and stars unimpeded. But Goddard soared far beyond this daring vision. He talked and wrote of experiments on the composition and circulation of the upper atmosphere of the Earth, of performing gammaray and ultraviolet observations of the Sun and stars from above the Earth’s atmosphere. He conceived of a space vehicle passing 1,000 miles above the surface of Mars—by a curious historical accident just the low point in the orbits of the Mariner 9 and Viking spacecraft. Goddard calculated that a reasonably sized telescope at such a vantage point would be able to photograph features tens of meters across on the surface of the Red Planet, which is the resolution of the Viking orbiter cameras. He conceived of slow interstellar flight at velocities and time scales just equivalent to that of the Pioneer 10 and 11 spacecraft, our first interstellar emissaries.
Goddard’s spirit soared higher still. He conceived, not casually but quite seriously, of solar-powered spacecraft, and in a time when any practical application of nuclear energy was publicly ridiculed, nuclear propulsion for spacecraft over vast interstellar distances. Goddard imagined a time in the far distant future when the Sun has grown cold and the solar system become uninhabitable, when manned interstellar spacecraft would be outfitted by our remote descendants, to visit the stars—not merely the nearby stars, but also remote star clusters in the Milky Way Galaxy. He could not imagine relativistic spaceflight and so hypothesized a method of suspended animation of the human crew or—even more imaginative—a means of sending the genetic material of human beings which would automatically, at some very distant time, be allowed to recombine and produce a new generation of people.
“With each expedition,” he wrote, “there should be taken all the knowledge, literature, art (in a condensed form), and description of tools, appliances, and processes, in as condensed, light, and indestructible a form as possible, so that the new civilization could begin where the old ended.” These final speculations, entitled “The Last Migration,” were sealed in an envelope with instructions to be read “only by an optimist.” And that he surely was—not a Pollyanna who chooses to ignore the problems and evils of our times, but rather, a man committed to the improvement of the human condition and the creation of a vast prospect for the future of our species.
Goddard’s dedication to Mars was never far from his mind. In the wake of one of his first experimental successes, he was induced to write a press release on the details of his launch and its ultimate significance. He wished to discuss spacecraft to Mars but was dissuaded on the ground that this was too fantastic.