by Arthur C. Clarke
In the thirty years during which I have been lecturing and writing on space and its exploration by man, I have seen the subject pass through two of the three phases which any novel or revolutionary idea has to undergo. These may be summed up as follows: 1: It’s utter nonsense. 2: It’s possible, but it’s not worth doing. 3: I said it was a good idea all the time. We are through phase one, we are thrashing about in the middle of phase two, and I hope to acceler-ate the transition into phase three. I consider acceleration essential, because today there are many critics of the space program who regard it as a kind of technological Olympics. They say, in essence, why shouldn’t all that money be spent here on earth, on housing or schools or hos-pitals? There is some truth in these arguments, which makes them difficult to answer glibly. History, far from being glib, provides an apposite lesson for those who refuse to see any value in leav-ing the problems of earth to explore the space around it. There was plenty to do in Europe when Columbus left it to embark on a voyage which most people then considered as foolhardy and needless as contempo-rary skeptics consider a voyage to Mars. There is still plenty to do in Europe. But the opening up of the new world did more to revive the stagnant European culture and economy than any internal action could possibly have done. In that sense, at least, Columbus was just in time. I believe that our reaching into space, as he reached across the Atlantic, is just in time. I cannot prove this; it is an act of faith But I welcome the so-called space-race, despite its high cost in money and human effort, for if we weren’t racing — if we had nothing to push against in the form of our Russian counter-parts — we wouldn’t be moving fast enough. We may be doing the right things for the wrong reasons, but the fact that they are the right things I believe can be proved.
A relatively new word in our vocabulary — spin-off — describes the benefits that accrue, sometimes unexpectedly, to everyday life from a purely scien-tific undertaking such as the space program. These spinoff benefits today are quite unpredictable, and are not so much in the form of hardware, marvelous though that is, as they are in the realm of knowledge and capability. The learning of things we will have to know to cross our last frontier can also contribute to improving the human condition on earth. Such improvements are essentially materialistic, else I imagine they would not qualify as improve-ments. A conspicuous example among the multitudi-nous space hardware now circling the earth can be found in the meteorological satellites. In the com-paratively short time they have been in orbit, they have practically revolutionized the science of weather forecasting. Weathermen can now receive current photographs of cloud formations and movements over large portions of the earth, taken from above all the weather — photographs that provide them with knowledge they have always wished for but have never before had any way of obtaining a ccurate weather forecasting, both immediate and long-range, is of immense importance not only to such obvious beneficiaries as farmers the world over, but to the general populace as well. In Ceylon, for example, where I live, life literally depends on the monsoon. As of now, no one can predict when it will break and deliver the water so essential to our crops Sometimes nature doesn’t deliver on time, and star-vation hits whole areas. Forecasting the monsoon’s arrival accurately is going to be of vast economic importance to half the human race. A more dramatic use of meteorological satellites has been in observing and tracking hurricanes. About 30 years ago a string of hurricanes which hit the Gulf States took about a thousand lives. This past summer, a similar storm roared up the Gulf of Mex-ico, but it was tracked every inch of the way in sat-ellite photographs — which gave enough warning of the storm’s approach to prevent worse loss of life than occurred. Although it is now impossible for the United States to be taken unaware by hurricanes, that unfortunately is not true elsewhere as yet. The cyclone that swept across the Bay of Bengal about three years ago caught a whole fishing fleet at sea and drowned a thousand fishermen. It even whipped a train off the causeway between India and Ceylon, dumping train and pas-sengers into the sea. That cyclone had been photo-graphed by the weather satellite Tiros, but no warn-ing network existed where it was then needed most. When ground facilities around the world match the capability of the globe-circling satellites, such dis-asters may be prevented, or at least mitigated Closely allied to the meteorological satellites are the environment satellites, which study and report on all types of ground resources. These, equipped with special cameras and sensing instruments, are beginning to tell us far more about the planet’s sur-face than even the best aerial surveys were able to show us. For example, some photographs reveal all types of air and water pollution, and can even detect areas of ocean fertility. Fishermen studying these sat-ellite pictures can actually see where they’re likely to find fish, and where the water has been polluted by land runoff, a potential destroyer of marine life One of the most important parameters of the ocean is its temperature. The Gulf Stream is familiar to everyone, but not everyone knows that its stream of relatively warm water often forms a thermal barrier to fish: they will swim within a few yards of it and follow it, but will not cross it. The enormous eco-nomic importance of that fact was demonstrated a few years ago when the Iceland fisheries were threat-ened with ruin because they couldn’t find the fish where they were supposed to be. The United States contributed an airplane equipped with infrared sen-sors, which successfully located the wandering Gulf Stream by detecting its heat. The fish had followed the stream, and the trawlers followed the fish. What was done then with an airplane can be done so much more effectively, and on a global scale, with environ-ment satellites. Millions of dollars a year could be saved — or made, depending on how you look at it — through this application of space hardware. Another kind of satellite orbiting aloft does not appear much in the news, but it is very much there and has already saved the American taxpayer several billions of dollars. This may be another example of doing the right thing for the wrong reasons, but wrong or not, it is a simple reality of life today that the major powers engage in continuous surveillance of each other by means of reconnaissance satellites. Before the advent of these orbiting eyes in the sky, we had only the ill-fated U-2 plane, and the con-viction that a serious “missile gap” existed between this country and Russia. Former President Johnson remarked off the record that the reconnaissance sat-ellites revealed the true extent of Russian missile development, showing it to be much less than was formerly supposed. Consequently, the planned ICBM force in this country was cut back to a level deemed adequate for security in the light of our new knowl-edge, and the taxpaper was saved literally billions of dollars in the process.
By far the most familiar item of hardware in the space program is the communications satellite. The general public, inured to an accelerating barrage of technical marvels, takes for granted the fact that it can flick on the TV set and watch Olympic games relayed live from Tokyo or Mexico City without ever considering for a moment the real marvels that make this possible. Although I have been credited with first suggesting communications satellites as early as 1945, I am impressed by the sheer sophistication of the equipment it has taken just to enable us to reach the point where we are now in real-time global communications. But present accomplishment is only a foretaste of what is to come. I believe that before the end of this century, we can have enough communications chan-nels through satellites to enable the whole human race to pair itself off and carry on simultaneous con-versations, perhaps a billion at one time. Will we really need such fantastic capability? I think we will, if not for human conversation, then certainly for channels linking computers, which are becoming more talkative than their human creators. I believe that some of the consequences of the communications satellite may be as profound — per-haps more profound — than those resulting from the invention of the telephone itself. For eventually, it will do away with much physical transportation. The world of the future will communicate, it will not commute. I think that is how we will solve some problems of the cities, how we will eliminate the traf-fic jams — not by covering the world with concrete, but simply by doing away with much of the traffic. There have been many studies of possible uses for “education” satellites. In an area like Brazil, for exam-ple, we can provide 12 channels of color TV to every school in the country. The cost of the satellite and ground equipment would work out to about one dollar per pupil per year. As I see it, the question is not, can th6 poorer countries afford communications satellites, but, can they afford any alternative?
Man in space a present need The social, cultural and even linguistic conse-quences of such direct broadcast satellites would be immeasurable. Imagine what would happen if one country were to establish a global system with just three transmitters in orbit, broadcasting directly; actually only two would reach about 95 percent of the human race. In the course of one generation, the language of that network would become the language of all mankind. This is not a matter of conquest or imposition of ideas; it is simply a matter of exposure and absorption. I believe that the ultimate impact of communica-tions satellites will be much like that of the railroad and the electric telegraph in building and unifying the sprawling new United States. What we are see-ing now, a hundred years later, is the repetition of this situation on a global scale. Instead of the rail-road and the telegraph, we now have the jet plane and the communications satellite. Ultimately the result will be parallel in unifying all people. Perhaps critics of the space program might con-cede some of these spinoff benefits. But what of manned space flight? What can man voyaging through space, exploring other worlds, bring back to help improve the human condition here at home? A sim-ple and immediate need for man in space is to help unmanned satellites in trouble. A couple of years ago, for example, this country launched its first orbit-ing astronomical observatory, which cost over $50 million. High above the murk and haze of our atmos-phere, it could have revealed the stars as they can never be seen on earth. It went into a perfect orbit —then its battery died. It is still up there, a beautiful, useless piece of hardware. And a man with a screw-driver might have fixed it could he have reached it. Another unmanned observatory, functioning perfect-ly, has now joined the dead one, but that kind of ex-perience is both disheartening and expensive. Not every “bird” sent aloft slips flawlessly into its intended orbit. Several communications satellites have gone astray and so cannot function as they are designed to. If we could send up manned rendezvous vehicles, the errant satellites could be nudged into the right orbit. It seems clear to me that the real ex-ploitation of space cannot come about until we have manned observatories, workshops and laboratories orbiting the earth, with crews rotating on regular shifts. In another decade we will have permanent stations in space, manned by teams equipped to re-place worn-out components or expendables in the satellites, which will be the workhorses of the future. The capability to do this is being developed auto-matically as a by-product of the Apollo program. In fact, we would have had to develop the Apollo equipment needed to take men to the moon, even if the moon wasn’t there at all. We would have to de-velop all the hardware, with the single exception of the lunar landing module, just to get into near space with substantial payloads to exploit the possibilities of orbiting satellites.
The Queen Elizabeth for three Until we have a fundamentally new type of launch vehicle, however, the exploitation of space on any practical scale is not going to be economically feasi-ble. The economics of space travel today are absurd. We must build a Saturn V rocket, driven by chemical combustion, 360 feet high and weighing 3,000 tons, just to take a small payload containing three men to the moon. This is like building the Queen Elizabeth to carry three passengers across the Atlantic and then sinking her after the maiden voyage. On the other hand, space travel is not going to be fantastically expensive. Actually, the energy require-ments to take one man the quarter million miles to our natural satellite are surprisingly low. If you ran your car continuously for 24 hours, it would do enough work to carry you to the moon. Electrically, it would take about 1,000 kilowatt hours of energy for the same trip. Just in terms of energy, the basic cost to take one man to the moon is $10. Today it costs $10 billion. Obviously, there is room for im-provement. I do not predict that we will ever have a $10 ticket to the moon, but the cost of this basic space voyage will come down by several orders of magni-tude in the 50 years just ahead. It is generally agreed among space experts that the key to practical space exploitation is the reusable vehicle. These can be flown up to orbit, then return to earth to be refueled and serviced, much as are today’s jet airliners. Reusable vehicles can open the way to space factories where entirely new manufac-turing processes can be carried out. A production plant orbiting in space can exploit two properties not available on earth: weightlessness and a limitless vac-uum. Engineers can now speculate about the fantastic manufacturing processes they could develop if noth-ing weighed anything. And as for electronic studies, instead of putting electron tube elements in a. vac-uum enclosed in a glass shell, we would put the scientists in a space suit and leave the tube elements out in the open. I’m sure that sometime in the next century we will have space hotels, like the Orbiter Hilton in the film 2001. More importantly, we will have space hospitals, opening whole new frontiers in medical science. Pre-liminary studies of the effects of weightlessness on animals and human beings already have shown some interesting biological changes. Some of these are beneficial, some may be harmful, but all will con-tribute to our knowledge of organic processes and cell growth. Obviously, one kind of cell growth in which all of medical science is interested is the yet unexplained and uncontrolled growth of cancer. I do not predict that we will ever find a cure for this dread malady in space, but I am certain that when such a cure is found, some of the knowledge that goes into it will have come from advances in medicine and biology resulting from the new disciplines of space medicine, developed in reaching for the moon.
Key io the solar system The first landfall beyond the atmosphere, of course, is the moon. It is a larger world than we tend to imagine, larger than Africa, and there are many geo-logical processes going on there which make it a more interesting and exciting place than it seemed only a few years ago. I’m sure that in 10 years there will be permanent bases on the moon, analogous to those now in the Antarctic. As soon as possible, we must locate lunar resources — water, oxygen-bearing ma-terial — so that bases there can be self-supporting. And what practical good can come of manned bases on the moon? For one thing, we will learn a tremen-dous amount about our own planet and the forces which formed it. For another, we may find recorded on the moon the history of the solar system. The earth’s surface has been turned over again and again hundreds of times since it was formed, so that much geological evidence of the far past has been lost. But on the moon, which has suffered little if any erosion like that on earth, digging down a few feet may take us back a billion years in time, or even farther back, to the time when the solar system was born. Beyond that, the key to exploring the rest of the solar system itself may lie in the moon It is 25 times easier to escape from the moon than it is from the earth, in terms of fuel or energy needed. Therefore, the moon may be literally a stepping-stone to the other planets — Mars, Venus, Jupiter, Saturn. We are lucky in having a sort of proving ground for our tech-niques so near at hand: only a second and a half from earth in terms of radio and only 50 hours or so in the time it actually takes to get there. Jupiter, the colossus of the solar system, now looks as though it will be the most interesting of all the planets. Some 11 times the diameter of the earth, it has a very deep, turbulent atmosphere consisting mostly of hydrogen, methane and ammonia. Until re-cently, most scientists thought that a planet covered by such a lethal mixture would be of no interest to anyone but biologists. But there has been a consider-able change of opinion in the last few years, for two reasons. First, because, although its outer atmosphere is very cold — as is the earth’s — beneath that the planet, whatever it may consist of, is actually quite warm, perhaps as warm as earth or even warmer. Second, the Jovian atmosphere now is identical with the one in which life originated on earth about two billion years ago. There may be an immense amount of early life on Jupiter — a living chapter from the remote past of creation.
Like, yet unlike Columbus The beneficial by-products of such exploration may be evident only in the long run, beyond the time of anyone now living. But the study of the inception and evolution of primitive organisms may give us invalu-able clues to maladies afflicting more complex organ-isms such as man. The moon is only a way-station, a launch-point, for the solar system at large; and this, I believe, is the frontier of the next century. Out on the planets there is several hundred times the land area of the earth, waiting to be explored. Perhaps much of it is inacces-sible or uninhabitable. The giant planets like Jupiter and Saturn may have no solid surfaces, and in any case will present an appalling challenge. But so did the voyages of Vespucci and Columbus, who really did not know exactly where they were going or what they might find when they arrived. We, at least, will know precisely where we are going, and we are beginning to have a clearer idea of what we may find at journey’s end.