As with most technologies, when something barely works, when it's the first of its kind, there's a natural tendency to improve it, develop it, exploit it. Soon there's such an institutional investment in the original technology, no matter how flawed, that it's very hard to move on to something better. NASA has almost no resources to pursue alternative propulsion technologies. That money would have to come out of near-term missions, missions which could provide concrete results and improve NASA's success record. Spending money on alternative technologies pays off a decade or two in the future. We tend to be very little interested in a decade or two in the future. This is one of the ways by which initial success can sow the seeds of ultimate failure; and is very similar to what sometimes happens in biological evolution. But sooner or later some nation—perhaps one without a huge investment in marginally effective technology—will develop effective alternatives.
Even before then, if we take a cooperative path, there will come a time—perhaps in the first decades of the new century and the new millennium—when an interplanetary spacecraft is assembled in Earth orbit, the progress in full view on the evening news. Astronauts and cosmonauts, hovering like gnats, guide and mate the prefabricated parts. Eventually the ship, tested and ready, is boarded by its international crew, and boosted to escape velocity. For the whole of the voyage to Mars and back, the lives of the crew members depend on one another, a microcosm of our actual circumstances down here on Earth. Perhaps the first joint interplanetary mission with human crews will be only a flyby or orbit of Mars. Earlier, robot vehicles, with aerobraking, parachutes, and retrorockets, will have set gently down on the Martian surface to collect samples and return them to Earth, and to emplace supplies for future explorers. But whether or not we have compelling, coherent reasons, I am sure—unless we destroy ourselves first—that the day will come when we humans set foot on Mars. It is only a matter of when.
According to solemn treaty, signed in Washington and Moscow on January 27, 1967, no nation may lay claim to part or all of another planet. Nevertheless—for historical reasons that Columbus would have understood well—some people are concerned about who first sets foot on Mars. If this really worries us, we can arrange for the ankles of the crew members to be tied together as they alight in the gentle Martian gravity.
The crews would acquire new and previously sequestered samples, in part to search for life, in part to understand the past and future of Mars and Earth. They would experiment, for later expeditions, on extracting water, oxygen, and hydrogen from the rocks and the air and from the underground permafrost—to drink, to breathe, to power their machines and, as rocket fuel and oxidizer, to propel the return voyage. They would test Martian materials for eventual fabrication of bases and settlements on Mars.
And they would go exploring. When I imagine the early human exploration of Mars, it's always a roving vehicle, a little like a jeep, wandering down one of the valley networks, the crew with geological hammers, cameras, and analytic instruments at the ready. They're looking for rocks from ages past, signs of ancient cataclysms, clues to climate change, strange chemistries, fossils, or—most exciting and most unlikely—something alive. Their discoveries are televised back to Earth at the speed of light. Snuggled up in bed with the kids, you explore the ancient riverbeds of Mars.
CHAPTER 16: SCALING HEAVEN
Who, my friend, can scale heaven?
—THE EPIC OF GILGAMESH
(SUMER, THIRD MILLENNIUM B.C.)
What?, I sometimes ask myself in amazement: Our ancestors walked from East Africa to Novaya Zemlya and Ayers Rock and Patagonia, hunted elephants with stone spearpoints, traversed the polar seas in open boats 7,000 years ago, circumnavigated the Earth propelled by nothing but wind, walked the Moon a decade after entering space—and we're daunted by a voyage to Mars? But then I remind myself of the avoidable human suffering on Earth, how a few dollars can save the life of a child dying of dehydration, how many children we could save for the cost of a trip to Mars—and for the moment I change my mind. Is it unworthy to stay home or unworthy to go? Or have I posed a false dichotomy? Isn't it possible to make a better life for everyone on Earth and to reach for the planets and the stars?
We had an expansive run in the '60s and '70s. You might have thought, as I did then, that our species would be on Mars before the century was over. But instead, we've pulled inward. Robots aside, we've backed off from the planets and the stars. 1 keep asking myself Is it a failure of nerve or a sign of maturity?
Maybe it's the most we could reasonably have expected. In a way it's amazing that it was possible at all: We sent a dozen humans on week-long excursions to the Moon. And we were given the resources to make a preliminary reconnaissance of the whole Solar System, out to Neptune anyway—missions that returned a wealth of data, but nothing of short-term, everyday, bread-on-the-table practical value. They lifted the human spirit, though. They enlightened us about our place in the Universe. It's easy to imagine skeins of historical causality in which there were no race to the Moon and no planetary program.
But it's also possible to imagine a much more serious devotion to exploration, because of which we would today have robot vehicles probing the atmospheres of all the Jovian planets and dozens of moons, comets, and asteroids; a network of automatic scientific stations emplaced on Mars would daily be reporting their findings; and samples from many worlds would be under examination in the laboratories of Earth—revealing their geology, chemistry, and perhaps even their biology. Human outposts might be already established on the near-Earth asteroids, the Moon, and Mars.
There were many possible historical paths. Our particular causality skein has brought us to a modest and rudimentary, although in many respects heroic, series of explorations. But it is far interior to what might have been—and what may one day be.
TO CARRY THE GREEN Promethean spark of Life with us into the sterile void and ignite there a firestorm of animate matter is the very destiny of our race," reads the brochure of something called the First Millennial Foundation. It promises, for $120 a year, "citizenship" in "space colonies—when the time comes." "Benefactors" who contribute more also receive "the undying gratitude of a star-flung civilization, and their name carved on the monolith to be erected on the Moon." This represents one extreme in the continuum of enthusiasm for a human presence in space. The other extreme—better represented in Congress—questions why we should be in space at all, especially people rather than robots. The Apollo program was a "moondoggle," the social critic Amitai Etzioni once called it; with the Cold War over, there is no justification whatever, proponents of this orientation hold, for a manned space program. Where in this spectrum of policy options should we be?
Ever since the United States beat the Soviet Union to the Moon, a coherent, widely understood justification for humans in space seems to have vanished. Presidents and Congressional committees puzzle over what to do with the manned space program. What is it for? Why do we need it? But the exploits of the astronauts and the moon landings had elicited—and for good reason—the admiration of the world. It would be a rejection of that stunning American achievement, the political leaders tell themselves, to back off from manned spaceflight. Which President, which Congress wishes to be responsible for the end of the American space program? And in the former Soviet Union a similar argument is heard: Shall we abandon, they ask themselves, the one remaining high technology in which we are still world leaders? Shall we be faithless heirs of Konstantin Tsiolkovsky, Sergei Korolev, and Yuri Gagarin?
The first law of bureaucracy is to guarantee its own continuance. Left to its own devices, without clear instructions from above, NASA gradually devolved into a program that would maintain profits, jobs, and perquisites. Pork-barrel politics, with Congress playing a leading role, became an increasingly powerful force in the design and execution of missions and long-term goals. The bureaucracy ossified. NASA lost its way.
On July 20, 1989, the twentieth anniversary of the Apollo 11 landing on the Moon, P
resident George Bush announced a long-term direction for the U.S. space program. Called the Space Exploration Initiative (SEI), it proposed a sequence of goals including a U.S. space station, a return of humans to the Moon, and the first landing of humans on Mars. In a later statement, Mr. Bush set 2019 as the target date for the first footfall on that planet.
And yet the Space Exploration Initiative, despite clear direction from the top, foundered. Four years after it was mandated, it did not even have a NASA office dedicated to it. Small and inexpensive lunar robotic missions—that otherwise might well have been approved—were canceled by Congress because of guilt by association with SEI. What went wrong?
One problem was the timescale. SEI extended five or so presidential terms of office into the future (taking the average presidency as one and a half terms). That makes it easy for a president to attempt to commit his successors, but leaves in considerable doubt how reliable such a commitment might be. SEI contrasted dramatically with the Apollo program—which, it might have been conjectured at the time it began, could have triumphed when President Kennedy or his immediate political heir was still in office.
Second, there was concern about whether NASA, which had recently experienced great difficulty in safely lifting a few astronauts 200 miles above the Earth, could send astronauts on an arcing year-long trajectory to a destination 100 million miles away and bring them back alive.
Third, the program was conceived exclusively in nationalist terms. Cooperation with other nations was not fundamental to either design or execution. Vice President Dan Quayle, who had nominal responsibility for space, justified the space station as a demonstration that the United States was "the world's only superpower." But since the Soviet Union had an operational space station that was a decade ahead of the United States, Mr. Quayle's argument proved difficult to follow.
Finally, there was the question of where, in terms of practical politics, the money was supposed to come from. The costs of getting the first humans to Mars had been variously estimated, ranging as high as $500 billion.
Of course, it's impossible to predict costs before you have a mission design. And the mission design depends on such matters as the size of the crew; the extent to which you take mitigating steps against solar and cosmic radiation hazards, or zero gravity; and what other risks you are willing to accept with the lives of the men and women on board. If every crew member has one essential specialty, what happens if one of them falls ill? The larger the crew, the more reliable the backups. You would almost certainly not send a full-time oral surgeon, but what happens if you need root canal work and you're a hundred million miles from the nearest dentist? Or could it be done by an endodontist on Earth, using telepresence?
Wernher von Braun was the Nazi-American engineer who, more than anyone else, actually took us into space. His 1952 book Das Marsprojekt envisioned a first mission with 10 interplanetary spacecraft, 70 crew members, and 3 "landing boats." Redundancy was uppermost in his mind. The logistical requirements, he wrote, "are no greater than those for a minor military operation extending over a limited theater of war." He meant to "explode once and for all the theory of the solitary space rocket and its little band of bold interplanetary adventurers," and appealed to Columbus' three ships without which "history tends to prove that he might never have returned to Spanish shores." Modern Mars mission designs have ignored this advice. They are much less ambitious than yon Braun's, typically calling for one or two spacecraft crewed by three to eight astronauts, with another robotic cargo ship or two. The solitary rocket and the little band of adventurers are still with us.
Other uncertainties affecting mission design and cost include whether you pre-emplace supplies from Earth and launch humans to Mars only after the supplies are safely landed; whether you can use Martian materials to generate oxygen to breathe, water to drink, and rocket propellants to get home; whether you land using the thin Martian atmosphere for aerobraking; the degree of redundancy in equipment thought prudent; the extent to which you use closed ecological systems or just depend on the food, water, and waste disposal facilities you've brought from Earth; the design of roving vehicles for the crew to explore the Martian landscape; and how much equipment you're willing to carry to test our ability to live off the land in later voyages.
Until such questions are decided, it's absurd to accept any figure for the cost of the program. On the other hand, it was equally clear that SEI would be extremely expensive. For all these reasons, the program was a nonstarter. It was stillborn.
There was no effective attempt by the Bush Administration to spend political capital to get SEI going.
The lesson to me seems clear: There may be no way to Send humans to Mars in the comparatively near future—despite the fact that it is entirely within our technological capability. Governments do not spend these vast sums just for science, or merely to explore. They need another purpose, and it must make real political sense.
It may be impossible to go just yet, but when it is possible, the mission, I think, must be international from the start, with costs and responsibilities equitably shared and the expertise of many nations tapped; the price must be reasonable; the time from approval to launch must fit within practical political timescales; and the space agencies concerned must demonstrate their ability to muster pioneering exploratory missions with human crews safely, on time, and on budget. If it were possible to imagine such a mission for less than $100 billion, and for a time from approval to launch less than 15 years, maybe it would be feasible. (In terms of cost, this would represent only a fraction of the annual civilian space budgets of the present spacefaring nations.) With aerobraking and manufacturing fuel and oxygen for the return trip out of Martian air, it's now beginning to look as if such a budget and such a timescale might actually be realistic.
The cheaper and quicker the mission is, necessarily the more risk we must be willing to take with the lives of the astronauts and cosmonauts aboard. But as is illustrated, among countless examples, by the samurai of medieval Japan, there are always competent volunteers for highly dangerous missions in what is perceived as a great cause. No budget, no timeline can be really reliable when we attempt to do something on so grand a scale, something that has never been done before. The more leeway we ask, the greater is the cost and the longer it takes to get there. Finding the right compromise between political feasibility and mission success may be tricky.
IT'S NOT ENOUGH to go to Mars because some of us have dreamt of doing so since childhood, or because it seems to us the obvious long-term exploratory goal for the human species. If we're talking about spending this much money, we must justify the expense.
There are now other matters—clear, crying national needs—that cannot be addressed without major expenditures; at the same time, the discretionary federal budget has become painfully constrained. Disposal of chemical and radioactive poisons, energy efficiency, alternatives to fossil fuels, declining rates of technological innovation, the collapsing urban infrastructure, the AIDS epidemic, a witches' brew of cancers, homelessness, malnutrition, infant mortality, education, jobs, health care—there is a painfully long list. Ignoring them will endanger the well-being of the nation. A similar dilemma faces all the spacefaring nations.
Nearly every one of these matters could cost hundreds of billions of dollars or more to address. Fixing infrastructure will cost several trillion dollars. Alternatives to the fossil-fuel economy clearly represent a multitrillion-dollar investment worldwide, if we can do it. These projects, we are sometimes told, are beyond our ability to pay. How then can we afford to go to Mars?
If there were 20 percent more discretionary funds in the U.S. federal budget (or the budgets of the other spacefaring nations), I probably would not feel so conflicted about advocating sending humans to Mars. If there were 20 percent less, I don't think the most diehard space enthusiast would be urging such a mission. Surely there is some point at which the national economy is in such dire straits that sending people to Mats is unco
nscionable. The question is where we draw the line. plainly such a line exists, and every participant in these debates should stipulate where that line should be drawn, what fraction of the gross national product for space is too much. I'd like the same thing done for "defense."
Public opinion polls show that many Americans think the NASA budget is about equal to the defense budget. In fact, the entire NASA budget, including human and robotic missions and aeronautics, is about 5 percent of the U.S. defense budget. How much spending for defense actually weakens the country? And even if NASA were cancelled altogether, would we free up what is needed to solve our national problems?
HUMAN SPACEFLIGHT In general—to say nothing of expeditions to Mars—would be much more readily supportable if, as in the fifteenth-century arguments of Columbus and Henry the Navigator, there were a profit lure.1 Some arguments have been advanced. The high vacuum or low gravity or intense radiation environment of near-Earth space might be utilized, it is said, for commercial benefit. All such proposals must be challenged by this question: Could comparable or better products be manufactured down here on Earth if the development money made available were comparable to what is being poured into the space program? Judging by how little money corporations have been willing to invest in such technology—apart from the entities building the rockets and spacecraft themselves—the prospects, at least at present, seem to be not very high.