The discovery of America ultimately made the fortune of this island, transformed our situation in the world. . . . As America prospered and became more important, so did we. . . . Within that community there is a natural shift of power and emphasis to the western side of the Atlantic. But already twice in our lifetime our country's existence has been assured by the preponderant partner. What sort of future could our small island expect looking out on a world riven between East and West, in the conflicts of giant land masses, without that assurance? . . . We owe this factor in our safety, the very condition of our lives, to the ambition and foresight, the enterprise and persistence, of our common ancestors, the Elizabethans.
—A.L. Rowse, The Elizabethans and America, 1959
The game of life is played not for money, but for children. The same is true of the contest of nations. Ultimately, victory can only be secured, and defined, by the generation of progeny.
In other chapters in this volume, authors have addressed the utility of space assets for pursuing military objectives such as support of communications, navigation, reconnaissance, missile or aircraft interception, or strike. Although the importance of such tactical applications of space technology for achieving superiority on the terrestrial battlefield can in no way be disparaged, this chapter considers the significance of the space endeavor and space itself with respect to the central strategic goal of securing ultimate victory for the American cause.
To use a naval analogy, the battlefield advantages offered by space technology compare to the application of superior seapower for such purposes as shore bombardment or close-in port blockade, both of which were of some utility to Britain in various European conflicts during its age of naval dominance. In contrast, the purposes addressed in this chapter compare to those by which the British took advantage of their maritime capacity to expand their language, culture, values, and society across the globe.
Anticipating the conflicts to come, a prescient late 19th-century writer once drew a pointed comparison between the strategic thinking styles of the contending European elites.1 The German General Staff, he observed, calculated their wars with regard to fortresses and railway schedules. The British, however, laid their plans in terms of "continents and centuries," and by virtue of this broader strategic grasp, would always ultimately defeat their more mentally limited opponents. Looking back today on both the course and outcomes of the two major wars of the 20th century, one cannot but be forcefully impressed by the penetrating nature of his assessment.
"Fortresses and railway schedules," or their modern-day equivalents, certainly have a place in military thinking. But if a nation is to prevail over the long haul, those entrusted with its fate must also consider matters of "continents and centuries." This is the central truth that must guide U.S. space policy if it is to be formulated adequately.
In the mid-1500s, at the time of accession of Queen Elizabeth I, England was a very minor power, insignificant in comparison with Spain, France, Poland, Austria, or the Ottoman Empire, inferior in significance even to Portugal or Venice. But as a result of the vision of leaders like Richard Hakluyt, Walter Raleigh, Humphrey Gilbert, and Elizabeth herself, a set of policy decisions was made and implemented at great cost and sacrifice to challenge Spain upon the high seas and thus make possible the creation of a new England on the other side of the Atlantic. If not for that and the colonization initiatives that followed, the individualistic humanist culture that Tudor England was in seed form would not have propagated to become the basis of advanced global society today. Indeed, if not for that, William Shakespeare, the Magna Carta, the Common Law, trial by jury, and other portentous aspects of Tudor society would today be mere historical footnotes, of no greater interest to the present age than the literature and culture of late medieval Croatia. If not for that, no one in the present age would likely be discoursing on space strategy at all.
In considering the success of the British program of overseas colonization in transforming both the English polity and English culture from insignificance to world dominance, it is useful to compare it not only with the policies of nonplaying contemporary great powers such as Turkey and Poland, but also to apparent colonizers such as Spain and France. While in retrospect it is clear enough that those powers that chose to obsess over affairs internal to the European arena while ignoring the continents to be won elsewhere were writing themselves out of the future, the difference in overseas colonization policies between those powers that did venture abroad is not as obvious. However, upon closer inspection, a dramatic difference between the overseas ventures of England and those of its transoceanic competitors emerges. Specifically, while Spain, France, Portugal, and Holland (as well as England) all set up overseas outposts for the purpose of extracting profits for the benefit of investors in Europe, only the English also set about seriously creating daughter countries, true new branches of English civilization. The Spanish sent conquistadors to Mexico and Peru to rule over natives enslaved to mine gold or silver, while the French sent adventurous traders to network with Canadian Indian tribes to obtain valuable fur pelts. However, the English sent families of settlers abroad to build farms, towns, universities, legislatures, and ultimately cities and nations. As a result, despite the fact that the population of the France of Louis XIV was four times that of contemporary England, by 1750 there were 2 million English-speaking people in North America but only 50,000 French. It was thus that the future of this continent and, to a significant degree, this planet, was decided.
But what about the rest of the planets? The Earth is not the only world. In the vast reaches of space, there are myriad others. The true prize in the great game is not the Persian Gulf, but the universe. The nation that first reaches out to colonize it is the one that will put its stamp upon the future.
Our New World
Among extraterrestrial bodies in our solar system, Mars is singular in that it possesses all the raw materials required to support not only life, but also a new branch of human civilization. This uniqueness is illustrated most clearly if Mars is contrasted with the Earth's Moon, the most frequently cited alternative location for extraterrestrial human colonization.
Unlike the Moon, Mars is rich in carbon, nitrogen, hydrogen, and oxygen, all in biologically readily accessible forms such as carbon dioxide gas, nitrogen gas, water ice, and permafrost.2 Carbon, nitrogen, and hydrogen are only present on the Moon in parts per million quantities. Oxygen is abundant on the Moon, but only in tightly bound oxides such as silicon dioxide, ferrous oxide, magnesium oxide, and alumina oxide, which require very high-energy processes to reduce.3 Current knowledge indicates that if Mars were smooth and all its ice and permafrost melted into liquid water, the entire planet would be covered with an ocean over 200 meters deep.4 This scenario contrasts strongly with the Moon, which is so dry that if concrete were found there, lunar colonists would mine it to get the water out. Thus, if plants could be grown in greenhouses on the Moon (an unlikely proposition, as the Moon's 2-week-long dark spell is unsuitable for most plants, and the absence of any atmosphere would make necessary very thick glass for solar flare shielding), most of their biomass material would have to be imported.
The Moon is also deficient in about half the metals of interest to industrial society (copper, for example), as well as many other elements of interest such as sulfur and phosphorus. Mars has every required element in abundance. Moreover, on Mars, as on Earth, hydrologic and volcanic processes have occurred that are likely to have consolidated various elements into local concentrations of high-grade mineral ore. Indeed, the geologic history of Mars has been compared to that of Africa, with very optimistic inferences as to its mineral wealth implied as a corollary.5 In contrast, the Moon has almost no history of water or volcanic action, with the result that it is basically composed of trash rocks with little differentiation into ores that represent useful concentrations of anything interesting.
Power could be generated on either the Moon or Mars with solar panels, and here the advantages of the Moon's clearer skies and closer proximity to the Sun than Mars roughly balance the disadvantage of large energy storage requirements created by the Moon's 28-day light/dark cycle. But if the desire was to manufacture solar panels so as to create a self-expanding power base, Mars holds an enormous advantage, as only Mars possesses the large supplies of carbon and hydrogen needed to produce the pure silicon required for making photovoltaic panels and other electronics. Also, there is no geologically purified source of silicon dioxide, such as sand, on the Moon. In addition, Mars has the potential for wind-generated power, while the Moon clearly does not. But both the Sun and wind offer relatively modest power potential—tens or at most hundreds of kilowatts here or there. To create a vibrant civilization, a richer power base is needed, and Mars has this both in the short and medium term in the form of its geothermal power resources, which offer the potential for large numbers of locally created electricity-generating stations in the 10 megawatt (10,000 kilowatt) class. In the long term, Mars will enjoy a power-rich economy based upon exploitation of its large domestic resources of deuterium fuel for fusion reactors. Deuterium is five times more common on Mars than it is on Earth, and tens of thousands of times more common on Mars than on the Moon.6
But the biggest problem with the Moon, as with all other airless planetary bodies and proposed artificial free-space colonies, is that sunlight is not available in a form useful for growing crops. A single acre of plants on Earth requires 4 megawatts (MW) of sunlight power; a square kilometer needs 1,000 MW. The entire world put together would not produce enough electric power to illuminate the farms of the state of Rhode Island. Growing crops with electrically generated light is economically hopeless. But natural sunlight cannot be used on the Moon or any other airless body in space unless the walls on the greenhouse are thick enough to shield out solar flares, a requirement that enormously increases the expense of creating crop land. Even accomplishing this requirement would do no good on the Moon, because plants will not grow in a light/dark cycle lasting 28 days.
But Mars has an atmosphere thick enough to protect crops grown on the surface from solar flares. Therefore, thin-walled inflatable plastic greenhouses protected by unpressurized ultraviolet-resistant hard-plastic shield domes can be used to rapidly create crop land on the surface. Even without the problems of solar flares and a month-long diurnal cycle, such simple greenhouses would be impractical on the Moon as they would create unbearably high temperatures. On Mars, in contrast, the strong greenhouse effect created by such domes would be precisely what is necessary to produce a temperate climate inside. Such domes up to 50 meters in diameter are light enough to be transported from Earth initially, and they eventually could be manufactured on Mars out of indigenous materials. Because all the resources to make plastics exist on Mars, networks of such 50- to 100-meter domes could be manufactured and deployed rapidly, opening up large areas of the surface to both shirtsleeve human habitation and agriculture. Looking further into the future, it will eventually be possible for humans to thicken Mars' atmosphere substantially by forcing the regolith to outgas its contents through a deliberate program of artificially induced global warming. Once that has been accomplished, the habitation domes could be almost any size, as they would not have to sustain a pressure differential between their interior and exterior. In fact, once that has been done, it will be possible to raise specially bred crops outside the domes.
The point is that unlike colonists on any other known extraterrestrial body, Martian colonists will be able to live on the surface, not in tunnels, and move about freely and grow crops in the light of day. Mars is a place where humans can live and multiply to large numbers, supporting themselves with products of every description made out of indigenous materials. Mars is thus a place where an actual civilization, not just a mining or scientific outpost, can be developed. And it is this civilization, grown in size and technological potency on a frontier planet with a surface area as large as all the continents of Earth put together, that will both radically tip the balance among those who remain behind on Earth and provide the pioneers with the craft and outlook required to push the human reach much further.
Thus, for our generation and those soon to follow, Mars is the new world. The nation that settles it is one whose culture, values, social forms, and ideas will provide the point of departure for the further development of human civilization as our species expands outward from its planet of origin to the innumerable others awaiting us in the infinite reaches of space.
The central strategic imperative of American space policy can thus be summarized in two words: colonize Mars.
The Question of Means
Some have said that sending humans to Mars is a venture for the far future. Such a point of view has no basis in fact. On the contrary, such a program is entirely achievable.7 From the technological point of view, we are ready. Despite the greater distance to Mars, we are much better prepared today to send humans to Mars than we were to launch humans to the Moon in 1961 when John F. Kennedy challenged the Nation to achieve that goal—and we were there 8 years later. Given the will, we could have our first teams on Mars within a decade.
The key to success will be to reject the policy of continued stagnation represented by shuttle-era thinking and return to the destination-driven Apollo method of planned operation that allowed the space agency to perform so brilliantly during its youth. In addition, we must take a lesson from our own pioneer past and adopt a "travel light and live off the land" mission strategy similar to the type that well served terrestrial explorers for centuries. The plan to explore the Red Planet in this way is known as Mars Direct (see figure 11–1). First, an unfueled Earth Return Vehicle (ERV) would be delivered to Mars, where it would manufacture its propellant from the Martian atmosphere. The crew then would fly to Mars in a tuna-can-shaped habitation module, which would also provide living quarters, a laboratory, and a workshop for a 1½-year Mars stay.
Figure 11–1. Artist concept of the Mars Direct plan.
Source: Robert Murray, Pioneer Astronautics
At an early launch opportunity—for example, 2014—a single heavy lift booster with a capability equal to that of the Saturn V used during the Apollo program is launched off Cape Canaveral and uses its upper stage to throw a 40-ton unmanned payload onto a trajectory to Mars. (Such a booster could be readily created by converting the shuttle launch stack, by deleting the Orbiter and replacing it with a payload fairing containing a hydrogen/oxygen rocket stage.) Upon arrival at Mars 8 months later, the spacecraft uses friction between its aeroshield and Mars' atmosphere to brake itself into orbit around the planet and then lands with the help of a parachute. This payload is the ERV. It flies out to Mars with its two methane/oxygen-driven rocket propulsion stages unfueled. It also carries 6 tons of liquid hydrogen cargo, a 100-kilowatt nuclear reactor mounted in the back of a methane/oxygen-driven light truck, a small set of compressors and an automated chemical processing unit, and a few small scientific rovers.
As soon as the craft lands successfully, the truck is telerobotically driven a few hundred meters away from the site, and the reactor is deployed to provide power to the compressors and chemical processing unit. The hydrogen brought from Earth can be quickly reacted with the Martian atmosphere, which is 95 percent carbon dioxide gas (CO2), to produce methane and water, thus eliminating the need for long-term storage of cryogenic hydrogen on the planet's surface. The methane so produced is liquefied and stored, while the water is electrolyzed to produce oxygen, which is stored, and hydrogen, which is recycled through the methanator. Ultimately, these two reactions (methanation and water electrolysis) produce 24 tons of methane and 48 tons of oxygen. Since this is not enough oxygen to burn the methane at its optimal mixture ratio, an additional 36 tons of oxygen is produced via direct dissociation of Martian CO2. The entire process takes 10 months, at the conclusion of which a total of 108 tons of methane/oxygen bipropellant will have been generated. This represents a leverage of 18:1 of Martian propellant produced compared to the hydrogen brought from Earth needed to create it. Ninety-six tons of the bipropellant will be used to fuel the ERV, while 12 tons are available to support the use of high-powered, chemically fueled long-range ground vehicles. Large additional stockpiles of oxygen can also be produced, both for breathing and for turning into water by combination with hydrogen brought from Earth. Since water is 89 percent oxygen (by weight), and since the larger part of most foodstuffs is water, this greatly reduces the amount of life support consumables that need to be hauled from Earth.
The propellant production having been successfully completed, in 2016 two more boosters lift off and throw their 40-ton payloads toward Mars. One of the payloads is an unmanned fuel-factory/ERV just like the one launched in 2014; the other is a habitation module carrying a crew of four, a mixture of whole food and dehydrated provisions sufficient for 3 years, and a pressurized methane/oxygen-powered ground rover. On the way to Mars, artificial gravity can be provided to the crew by extending a tether between the habitat and the burnt-out booster upper stage and spinning the assembly.
Upon arrival, the manned craft drops the tether, aerobrakes, and lands at the 2014 landing site, where a fully fueled ERV and fully characterized and beaconed landing site await it. With the help of such navigational aids, the crew should be able to land right on the spot. However, if the landing is off course by tens or even hundreds of kilometers, the crew can still achieve the surface rendezvous by driving over in their rover. If they are off by thousands of kilometers, the second ERV provides a backup.
However, assuming the crew lands and rendezvous as planned at site number one, the second ERV will land several hundred kilometers away to start making propellant for the 2018 mission, which in turn will fly out with an additional ERV to open up Mars landing site number three. Thus, every other year, two heavy-lift boosters are launched—one to land a crew, and the other to prepare a site for the next mission—for an average launch rate of just one booster per year to pursue a continuing program of Mars exploration. Since in a normal year, we can launch about six shuttle stacks, this would only represent about 16 percent of the U.S. launch capability and would clearly be affordable. In effect, this "live off the land" approach removes the manned Mars mission from the realm of mega-spacecraft fantasy and reduces it in practice to a task of comparable difficulty to that faced in launching the Apollo missions to the Moon.
The crew will stay on the surface for 1½ years, taking advantage of the mobility afforded by the high-powered, chemically driven ground vehicles to accomplish a great deal of surface exploration. With a 12-ton surface fuel stockpile, they have the capability for over 24,000 kilometers worth of traverse before they leave, giving them the kind of mobility necessary to conduct a serious search for evidence of past or present life on Mars—an investigation key to revealing whether life is a phenomenon unique to Earth. Since no one has been left in orbit, the entire crew will have available to them the natural gravity and protection against cosmic rays and solar radiation afforded by the Martian environment, and thus there will not be the strong driver for a quick return to Earth that plagues alternative Mars mission plans based upon orbiting mother ships with small landing parties. At the conclusion of their stay, the crew returns to Earth in a direct flight from the Martian surface in the ERV. As the series of missions progresses, a string of small bases will be left behind on the Martian surface, opening up broad stretches of territory to human cognizance.
In essence, by taking advantage of the most obvious local resource available on Mars—its atmosphere—the plan allows accomplishment of a manned Mars mission with what amounts to a lunar-class transportation system. By eliminating any requirement to introduce a new order of technology and complexity of operations beyond those needed for lunar transportation to accomplish piloted Mars missions, the plan can reduce costs by an order of magnitude and advance the schedule for the human exploration of Mars by a generation.
Exploring Mars requires no miraculous new technologies, no orbiting spaceports, and no gigantic interplanetary space cruisers. We do not need to spend the next 30 years with a space program mired in impotence, spending large sums of money, and taking occasional casualties while the same missions to nowhere are flown over and over again and professional technologists dawdle endlessly without producing any new flight hardware. We simply need to choose our destination and, with the same combination of vision, practical thinking, and passionate resolve that served us so well during Apollo, do what is required to get there.
We can establish our first small outpost on Mars within a decade. We and not some future generation can have the eternal honor of being the first pioneers of this new world for humanity. All that is needed is present-day technology, some 19th-century industrial chemistry, a solid dose of common sense, and a little bit of moxie.
The Question of Morale
Of the requirements for a successful Mars program, it is the moxie that currently seems hardest to come by. NASA recently made what was intended to be a grand announcement that it was setting its sights on returning astronauts to the Moon by 2020—just a bit over half a century after Americans landed there the first time. NASA gave various reasons for its Moonbase plan, none of which made any sense. The stated scientific goals were trivial compared to those that could be addressed on Mars, and due to its extreme poverty of resources, the Moon is a very poor candidate for human settlement. NASA's claim that nevertheless, the Moon might be a good place to practice space exploration and settlement in preparation for going to Mars (where such activities might actually be possible) was risible. Practice for Mars missions could be done for a tiny fraction of the cost (or three orders of magnitude more practice could be accomplished for the same cost) in the Arctic, so NASA clearly is not aiming for the Moon in order to practice for Mars. On the contrary, the primary purpose of the Moon program appears to be to give NASA a driving programmatic goal that does not require embracing the challenge of Mars. Indeed, given the lengthy schedule to the first return landing as advertised for the lunar program (roughly twice as long as it took NASA to accomplish the same feat during the age of slide rules and rotary telephones), one may question whether the current NASA lunar program even includes a willingness to take on the challenge of going to the Moon.8Rather, like President George W. Bush's announcement of a plan to balance the Federal budget by 2012 (that is, 4 years after he left office), it seems more like a recommendation that somebody else should take on the responsibility of acting bravely.
The question of the reassertion of the American spirit thus emerges as the critical variable that will determine victory or defeat for our nation. How can the space program contribute toward that end? Certainly not by choosing timid goals. Our military space activities can do much to assist national defense, but what we really need is a space program that makes it clear to all that ours is a nation that is truly worth defending.
In September 1962, even as the United States headed toward a decisive confrontation with the Soviet Union in the Cuban missile crisis, President John F. Kennedy gave a speech concerning space policy at Rice University:
We choose to go to the Moon! We choose to go to the Moon in this decade and do the other things, not because they are easy but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win. . . . This is in some measures an act of faith and vision, for we do not know what benefits await us. . . . But space is there and we are going to climb it.
That is the spirit that built this nation, won the West, achieved our victories, and really got us to the Moon. It is the spirit we desperately need to find again today. But if we are to be as great a people as we once were, we need to act as we once did. For the present age, that means choosing to accept the challenge of Mars. A humans-to-Mars program would be a direct reassertion of the American pioneer spirit. It also would be a profound statement that we, both as a species and as a nation, are living not at the end of our history, but at the beginning of our history—that we choose to continue to be a people whose great deeds will be reported in newspapers, and not just in museums. It is by making and honoring that statement that we will create the means for victory, both now and for ages to come.