by Carl Sagan
Despite many NASA press releases, much of the space program and almost all of its space science and applications program are in the long run not gimmicky or parochial in perspective. Indeed, they share a community of philosophical, exploratory, and human interest with many segments of American society – even segments that are in strong mutual disagreement on many issues. The cost of space exploration seems very modest compared with its potential returns.
9. Space Exploration as a Human Enterprise
III. The Historical Interest
In the long view, the greatest significance of space exploration is that it will irreversibly alter history. As we mentioned in Chapter 1, the group with which Man identifies has gradually broadened during this history of mankind. Today the bulk of the world's population has at least a major personal identification with national superstates. While progress has not been smooth, and there are occasional reversals, the trend is clearly toward a group identification with mankind as a whole. Space exploration can hasten this identification. Astronauts and cosmonauts have remarked with great feeling about the beauty and serenity of the Earth viewed from space. For many of them, a flight into space has been a religious experience, transfiguring their lives. National boundaries do not appear in photographs of Earth from space. As Arthur C. Clarke somewhere remarked, it is difficult to imagine even the most fervent of nationalists not reconsidering his views as he sees the Earth fade from a faint crescent to a tiny point of light, lost among millions of stars.
Space exploration provides a calibration of the significance of our tiny planet, lost in a vast and unknown universe. The search for life elsewhere will almost surely drive home the uniqueness of Man: The winding, unsure, improbable, evolutionary pathway that has brought us to where we are; and the improbability of finding – even in a universe populated with other intelligences – one with a form very much like our own. In this perspective, the similarities among men will stand out overwhelmingly against our differences.
There is a practical geocentrism to our everyday life. We still talk about the Sun rising and setting rather than the Earth turning. We still think of the universe organized for our benefit and populated only by us. Space exploration will bring also a little humility.
Harold Urey has perceptively referred to the space program as a kind of contemporary pyramid-building. Seen in the context of Pharaonic Egypt, the analogy seems particularly apt, for the pyramids were an attempt to deal with problems of cosmology and immortality. In the long historical perspective, this is precisely what the space program is about. The footprints left by astronauts on the Moon will survive a million years, and the miscellaneous instruments and packing cases left there may last as long as the Sun.
On the other hand, the pyramids are monumental and, we today believe, futile efforts to insure the survival after death of one man, the Pharaoh. Perhaps a better analogy is with the ziggurats, the terraced towers of the Sumerians and Babylonians – the places where the gods came down to Earth and the population as a whole transcended everyday life. There is no doubt a little of the pyramid in the great rocket boosters; but I think their ultimate significance is more likely to be as contemporary ziggurats.
A society engaged in a relatively modest, peaceful, and intellectually significant exploration of its surroundings garners thereby the possibility of achieving greatness. It is difficult to prove such causal chains, and, historically, there are no one-to-one correlations. But it is remarkable that the nations and epochs marked by the greatest flowering of exploration are also marked by the greatest cultural exuberance. In part, this must be because of the contact with new things, new ways of life, and new modes of thought unknown to a closed culture, with its vast energies turned inward.
There are examples from the Biblical Near East, from Periclean Athens, and from other times, but I am most taken by the example of the age of European exploration and discovery. The vernacular languages of France, England, and Iberia found a definitive literary expression at the same time that the earliest transatlantic voyages of discovery were occurring. Rabelais and Montaigne in France; Shakespeare, Milton, and the translators of the King James Bible in England; Cervantes and Lope de Vega in Spain; Camoens in Portugal, all date from this period. From the writings of Francis Bacon it is clear that exposure to new parts of the world had a profound influence on the thinking of the times. This period saw the invention of such fundamental instruments as the telescope, the microscope, the thermometer, the barometer, and the pendulum clock.
It was also the epoch of Galileo (1564-1642), who, while not resident in one of the new exploratory nations, was closely tied to one of them – Holland, where the telescope that he improved upon was first invented. Many of the works of graphic art during this period – for example, those of Hieronymus Bosch and El Greco – reflect the spirit of change that permeated the times. It was the era of the establishment of modern physics by Isaac Newton. Descartes, Hobbes, and Spinoza – pivotal individuals in the history of philosophy – flourished. In the activities and writings of da Vinci, Gilbert, Galileo, and Bacon, the period also corresponds to the origin of the experimental method in science.
An interesting case history is provided by Holland, a country that has provided more than its fair share of men of learning and culture. If there was one moment of cultural efflorescence in Holland, it was the period centered around the last half of the seventeenth century. Iberian ports were inaccessible to the Dutch Republic because of the war between France and Spain. Forced to find its own sources of trade, Holland founded the Dutch East and West India Companies. A significant fraction of the national resources was put into seafaring; one consequence was that Holland became – for the only time in its history – a world power. Because of these ventures, Dutch is spoken in Indonesia today, and several individuals of Dutch ancestry rose to the Presidency of the United States. Far more important is the fact that, during the same period, Vermeer and Rembrandt, Spinoza and van Leeuwenhoek flourished in Holland. It was a tightly knit society: Van Leeuwenhoek, was, in fact, the executor of Vermeer's estate. Holland was the most liberal and least authoritarian nation in Europe during this time.
In all the history of mankind, there will be only one generation that will be first to explore the Solar System, one generation for which, in childhood, the planets are distant and indistinct discs moving through the night sky, and for which, in old age, the planets are places, diverse new worlds in the course of exploration.
There will be a time in our future history when the Solar System will be explored and inhabited. To them, and to all who come after us, the present moment will be a pivotal instant in the history of mankind. There are not many generations given an opportunity as historically significant as this one. The opportunity is ours, if we but grasp it. To paraphrase K. E. Tsiolkovsky, the founder of astronautics: The Earth is the cradle of mankind, but one cannot live in the cradle forever.
A human infant begins to achieve maturity by the experimental discovery that he is not the whole of the universe. The same is true of societies engaged in the exploration of their surroundings. The perspective carried by space exploration may hasten the maturation of mankind – a maturation that cannot come too soon.
Part Two:
THE SOLAR SYSTEM
There was a time – and very recently – when the idea of the possibility of learning the composition of the celestial bodies was considered senseless even by prominent scientists and thinkers. That time has now passed. The idea of the possibility of a closer, direct study of the universe will today, I believe, appear still wilder. To step out onto the soil of asteroids, to lift with your hand a stone on the moon, to set up moving stations in ethereal space, and establish living rings around the earth, the moon, the sun, to observe Mars from a distance of several tens of versts, to land on its satellites and even on the surface of Mars – what could be more extravagant! However, it is only with the advent of reactive vehicles that a new and great era in astronomy will begin, the epoch of
a careful study of the sky… The prime motive of my life is to do something useful for people… That is why I have interested myself in things that did not give me bread or strength. But I hope that my studies will, perhaps soon but perhaps in the distant future, yield society mountains of grain and limitless power.
-K. E. Tsiolkovsky, 1912
10. On Teaching the First Grade
A friend in the first grade asked me to come to talk to his class, which, he assured me, knew nothing about astronomy but was eager to learn. With the approval of his teacher, I arrived at his school in Mill Valley, California, armed with twenty or thirty color slides of astronomical objects – the Earth from space, the Moon, the planets, exploding stars, gaseous nebulae, galaxies, and the like – which I thought would amaze and intrigue and, perhaps to a certain extent, even educate.
But before I began the slide show for these bright-eyed and cherubic little faces, I wanted to explain that there is a big difference between stating what science has discovered and describing how scientists found it all out. It is pretty easy to summarize the conclusions. It is hard to relate all the mistakes, false leads, ignored clues, dedication, hard work, and painful abandonment of earlier views that go into the initial discovery of something interesting.
I began by saying, "Now you have all heard that the Earth is round. Everybody believes that the Earth is round. But why do we believe the Earth is round? Can any of you think of any evidence that the Earth is round?"
For most of the history of mankind, it was reverently held that the Earth is flat – as is entirely obvious to anyone who has stood in a Nebraska cornfield around planting time. The concept of a flat Earth is still built into our language in such phrases as "the four corners of the Earth." I thought I would stump my little first-graders and then explain with what difficulty the sphericity of Earth had come into general human consciousness. But I had underestimated the first grade of Mill Valley.
"Well," asked a moppet in the sort of one-piece coverall worn by railroad engineers, "what about this business of a ship that's sailing away from you, and the last thing you see is the master, or whatever it's called, that holds up the sail? Doesn't that mean that the ocean has to be curved?"
"What about when there's an ellipse of the Moon? That's when the Sun is behind us and the shadow of the Earth is on the Moon, right? Well, I saw an ellipse. That shadow was round, it wasn't straight. So the Earth has to be round."
"There's better proof, much better proof," offered another. "What about that old guy who sailed around the world – Majello? You can't sail around the world if it isn't round, right? And people today sail around the world and fly around the world all the time. How can you fly around the world if it isn't round?"
"Hey, listen, you kids, don't you know there's pictures of the Earth?" added a fourth. "Astronauts have been in space, they took pictures of the Earth; you can look at the pictures, the pictures are all round. You don't have to use all these funny reasons. You can see that the Earth is round."
And then, as the coup de grâce, one pinafored little girl, recently taken on an outing to the San Francisco Museum of Science, casually inquired, "What about the Foucault pendulum experiment?"
It was a very sobered lecturer who went on to describe the findings of modern astronomy. These children were not the offspring of professional astronomers or college teachers or physicians or the like. They were apparently ordinary first-grade children. I very much hope – if they can survive twelve to twenty years of regimenting "education" – that they will hurry and grow up and start running things.
Astronomy is not taught in the public schools, at least in America. With a few notable exceptions, a student can pass from first to twelfth grade without ever encountering any of the findings or reasoning processes that tell us where we are in the universe, how we got here, and where we are likely to be going; without any confrontation with the cosmic perspective.
The ancient Greeks considered astronomy one of the half dozen or so subjects required for the education of free men. I find, in discussions with first-graders and hippie communards, congressmen and cab drivers, that there is an enormous untapped reservoir of interest and excitement in things astronomical. Most newspapers in America have a daily syndicated astrology column. How many have a daily syndicated astronomy column, or even a science column?
Astrology pretends to describe an influence that pervades people's lives. But it is a sham. Science really influences people's lives, and in only a slightly less direct sense. The enormous popularity of science fiction and of such movies as 2001: A Space Odyssey is indicative of this unexploited scientific enthusiasm. To a very major extent, science and technology govern, mold, and control our lives – for good and for ill. We should make a better effort to learn something about them.
11. "The Ancient and Legendary Gods of Old"
The sorts of scientific problems that I am involved in – the environments of other planets, the origin of life, the possibility of life on other worlds – engage the popular interest. This is no accident. I think all human beings are excited about these fundamental problems, and I am lucky enough to be alive at a time when it is possible to perform scientific investigation of some of these problems.
One result of popular interest is that I receive a great deal of mail, all kinds of mail, some of it very pleasant, such as from the people who wrote poems and sonnets about the plaque on Pioneer 10; some of it from schoolchildren who wish me to write their weekly assignments for them; some from strangers who want to borrow money; some from individuals who wish me to check out their detailed plans for ray guns, time warps, spaceships, or perpetual motion machines; and some from advocates of various arcane disciplines such as astrology, ESP, UFO-contact stories, the speculative fiction of von Danniken, witchcraft, palmistry, phrenology, tea-leaf reading, Tarot cards, the I-Ching, transcendental meditation, and the psychedelic drug experience. Occasionally, also, there are sadder stories, such as from a woman who was talked to from her shower head by inhabitants of the planet Venus, or from a man who tried to file suit against the Atomic Energy Commission for tracking his every movement with "atomic rays." A number of people write that they can pick up extraterrestrial intelligent radio signals through the fillings in their teeth, or just by concentrating in the right way.
But over the years there is one letter that stands out in my mind as the most poignant and charming of its type. There came in the post an eighty-five-page handwritten letter, written in green ballpoint ink, from a gentleman in a mental hospital in Ottawa. He had read a report in a local newspaper that I had thought it possible that life exists on other planets; he wished to reassure me that I was entirely correct in this supposition, as he knew from his own personal knowledge.
To assist me in understanding the source of his knowledge, he thought I would like to learn a little of his personal history – which explains a good bit of the eighty-five pages. As a young man in Ottawa, near the outbreak of World War II, my correspondent chanced to come upon a recruiting poster for the American armed services, the one showing a goateed old codger pointing his index finger at your belly button and saying, "Uncle Sam Wants You." He was so struck by the kindly visage of gentle Uncle Sam that he determined to make his acquaintance immediately. My informant boarded a bus to California, apparently the most plausible habitation for Uncle Sam. Alighting at the depot, he inquired where Uncle Sam could be found. After some confusion about surnames, my informant was greeted by unpleasant stares. After several days of earnest inquiry, no one in California could explain to him the whereabouts of Uncle Sam.
He returned to Ottawa in a deep depression, having failed in his quest. But almost immediately, his life's work came to him in a flash. It was to find "the ancient and legendary gods of old," a phrase that reappears many times throughout the letter. He had the interesting and perceptive idea that gods survive only so long as they have worshipers. What happens then to the gods who are no longer believed in, the gods, for example, of ancient Gree
ce and Rome? Well, he concluded, they are reduced to the status of ordinary human beings, no longer with the perquisites and powers of the godhead. They must now work for a living – like everyone else. He perceived that they might be somewhat secretive about their diminished circumstances, but would at times complain about having to do menial labor when once they supped at Olympus. Such retired deities, he reasoned, would be thrown into insane asylums. Therefore, the most reasonable method of locating these defrocked gods was to incarcerate himself in the local mental institution – which he promptly did.
While we may disagree with some of the steps in his reasoning, we probably all agree that the gentleman did the right thing.
My informant decided that to search for all the ancient and legendary gods of old would be too tiring a task. Instead, he set his sights on only a few: Jupiter, Mercury, and the goddess on the obverse face of the old British penny – not everyone's first choice of the most interesting gods, but surely a representative trio. To his (and my) astonishment, he found – incarcerated in the very asylum in which he had committed himself – Jupiter, Mercury, and the goddess on the obverse face of the old English penny. These gods readily admitted their identities and regaled him with stories of the days of yore when nectar and ambrosia flowed freely.
And then my correspondent succeeded beyond his hopes. One day, over a bowl of Bing cherries, he encountered "God Almighty," or at least a facsimile thereof. At least the Personage who offered him the Bing cherries modestly acknowledged being God Almighty. God Almighty luckily had a small spaceship on the grounds of the asylum and offered to take my informant on a short tool around the Solar System – which was no sooner said than done.