Another Run at the Moon - The Value of the Moon: How to Explore, Live, and Prosper in Space Using the Moon's Resources (2016)

The Value of the Moon: How to Explore, Live, and Prosper in Space Using the Moon's Resources (2016)

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Another Run at the Moon

With the completion of the successful Department of Defense Clementine mission, the Moon was again viewed as a destination of value. Both Lawrence Livermore and the Naval Research Laboratory prepared for a Clementine II asteroid flyby mission, the unmet objective of the first mission due to a technical failure with Clementine’s thrusters after it departed the Moon. Some on the study team proposed a mission profile that would mirror the plan of the first Clementine, an asteroid flyby followed by insertion into lunar orbit. The objective would be to map the Moon at greater resolution with additional instruments and follow up on the discoveries made by the first Clementine. This renewed lunar attention was not without detractors, who questioned what Clementine had found. Congress appropriated funds for the mission in 1997, but plans to fly it were scuttled when President Bill Clinton used his newly acquired line-item veto to zero out funds for Clementine II. The Supreme Court subsequently declared the line-item veto unconstitutional, but too late to save the Clementine II mission.

Around this time, NASA called for proposals to the Discovery program, a new series of small planetary missions, cost-capped at $150 million.1 This mission series was NASA’s attempt to emulate the Faster-Cheaper-Better paradigm that Clementine encapsulated. The new NASA administrator Dan Goldin was renowned for his advocacy of the FBC mode of business. The Discovery program received dozens of mission proposals. A single planetary scientist, called the principal investigator (PI), led each proposal. In 1995, NASA picked Lunar Prospector (LP), led by Alan Binder, as the first Discovery mission, deeming it the least expensive, least risky mission proposal it had received, requiring only a small operations team. Its selection also avoided having the Clementine team again set foot on what NASA thought to be its turf, since a second NRL Clementine multiple asteroid flyby of comparable cost was also proposed.

The particle and geochemical sensors of LP perfectly complemented the multispectral images and laser altimetry data obtained by Clementine. Combined, these two missions gave us our first global look at lunar mineral and chemical compositions, surface topography and gravity, and regional geology and produced the data sets of the never-flown Lunar Polar Orbiter, the mission scientists had long desired. For example, we found that high concentrations of radioactive elements in the lunar crust are localized in the Procellarum topographic depression of the western near side, an unusual global asymmetry that is still unexplained. More importantly, LP’s neutron spectrometer found high concentrations of hydrogen at both poles in roughly equal quantities. The neutron experiment only measures the concentration of elemental hydrogen, not its physical state—that is, whether it is present in the form of water ice or excess solar wind gas in the cool polar regolith. From this information, as well the results on lunar polar lighting and the bistatic radar from Clementine, the evidence continued to mount that something very interesting was present at both poles of the Moon.2

The Moon’s spin axis is inclined 1.5° from the normal to the ecliptic plane, a nearly perpendicular orientation; this means that the Sun always hovers near the horizon at the poles of the Moon. The apparent angular width of the Sun at the Earth-Moon distance is about 0.5° of arc, so sometimes the Sun could be above the horizon and at other times, below it. But because the Moon’s surface is rough and irregular, with large craters and basins, there are areas near the poles that in theory could see either permanent sunlight or permanent darkness. Clementine spent only seventy-one days in lunar orbit during the southern winter solstice, so it provided illumination data for only part of the lunar year. Nonetheless, analysis showed that small areas near the crater Shackleton, located near the south pole of the Moon, were sunlit more than 70 percent of the southern winter day. Three areas near the north pole were illuminated 100 percent of the day (northern summer). Data for the opposite seasons were not obtained.

An intense scientific debate over the existence of ice at the lunar poles spanned most of the decade around the turn of the millennium. The lunar ice controversy stemmed from the ambiguity of radar CPR as an indicator of both surface physical properties and composition. Because the data were nondeterminative, they proved fertile ground for intense argument. A paper presented at the 1995 Lunar Science Conference in Houston described the results of high resolution imaging of the lunar south pole by the large dish antenna at Arecibo, Puerto Rico. These images were able to peek into the totally sunless areas near the pole. Interestingly, small regions of high diffuse backscatter were seen.3 This high diffuse backscatter, called circular polarization ratio, or CPR, is consistent with a surface composed of water ice, a high concentration of angular blocks, or both. Based on our result from the bistatic experiment, the Clementine team preferred the water ice interpretation, while others in the radar planetary science community argued for an origin from surface roughness.

The new LP neutron data clearly showed an excess of hydrogen at the poles, but the surface resolution of its hydrogen concentration maps was very low and we could not be certain whether the signal was caused by a large area of relatively low concentration—that is, solar wind gases implanted in the regolith—or by small, isolated zones of very high concentration such as ice in permanently dark areas. This controversy raged on as we tried to design, build, and fly a small imaging radar to the Moon to follow up on the Clementine and LP discoveries. Despite proposals for small NASA robotic missions, European Space Agency interest, and even some proposed commercial missions, no flight opportunities were to arise until late in 2003.

The greatest remaining unknowns were about the poles, those areas where we had found permanent darkness, possible permanent sunlight, and enhancement of hydrogen concentration, possibly indicating the presence of water ice in the dark regions. All of these new insights showed that the Moon was more complex and interesting than we had thought. A key discovery was the zones of extended sunlight. Finding areas on the surface that receive illumination for almost all of the lunar day removed one of the biggest hurdles to human habitation of the Moon: the need to provide a power source for electricity and heat during the fourteen-day nighttime. Nuclear power is best suited to the task, but the high costs of such power, both technical and societal, made lunar return unaffordable.

In contrast, the discovery of areas where power could be generated constantly by solar arrays now made extended stays on the Moon by people feasible. In addition, illuminated terrain—even by sunlight at grazing incidence—makes the extremely cold lunar night tolerable. Areas of constant sunlight near deposits of water ice create “oases” near the poles of the Moon where human habitation is possible and perhaps even profitable.

There was an interesting coda to the Lunar Prospector mission. After lowering its orbit to about 20 kilometers, as close as it is possible to orbit the Moon without running into some of its higher mountaintops, and collecting some high-resolution data from this close orbit, the spacecraft was deliberately crashed into a crater near the south pole on July 31, 1999. The objective of this effort was to kick up material from the impact to try to detect the polar water in the ejecta cloud with telescopes on Earth. Unfortunately, no ejecta were observed, so the debate over lunar polar water continued. (The same experiment was repeated ten years later during the LCROSS mission, with more productive results.) The LP spacecraft did carry an unusual cargo, however: some of Gene Shoemaker’s ashes.4 The urn and the LP spacecraft now rest in the floor of a crater near the south pole, subsequently given the name Shoemaker, a fitting tribute to Gene and his contributions to the study and exploration of the Moon.

We believed that we had found water at the poles of the Moon. Now we needed a commitment to go back to verify the new findings.

Mars Mania

Robotic missions to Mars have dominated the last twenty years of planetary exploration, an emphasis stemming in part from the planetary science community’s efforts to fly a series of robotic missions that will eventually lead to the return of samples from Mars to Earth, an ambitious and very expensive proposition. With NASA’s robotic spaceflight program still under intense scrutiny after the failures of the initial Hubble Space Telescope mission and JPL’s 1993 Mars Observer spacecraft, Administrator Dan Goldin, a booster of both human Mars missions and the search for life, was unable to convince the Clinton administration or Congress to pony up enough money to fund an ambitious Mars sample return effort.5 Undeterred, Goldin applied the FBC paradigm to Mars missions and moved forward with the Mars Pathfinder mission, a small rover called Sojourner that landed on Mars using a parachute and airbags deployed for final impact. Sojourner took some images and made a rudimentary chemical analysis of the soil. Pathfinder, although technically successful, did not fundamentally advance our knowledge and understanding of Mars and its surface processes and history, thus missing out on the “better”—or even the “good enough”—part of FBC.

An event that would concentrate everyone’s attention on Mars during the 1990s turned out not to be from any space mission but from a laboratory right here on Earth. We had known for some time that a rare group of meteorites, the Shergottite-Nahklaite-Chassignite group (SNC), had unusual chemical properties and relatively young ages of crystallization. Analysis of these rocks found trapped argon within them identical in composition to analysis of the martian atmosphere made in 1976 by the Viking spacecraft. Scientists concluded that these meteorites are pieces of the martian crust, thrown into space by an impact on Mars that eventually made their way to Earth. The composition of these meteorites seemed to fit what we had inferred from Viking and remote sensing about the composition of Mars. These meteorites had ages much younger than most meteorites, nearly all of which formed 4.6 billion years ago, and lunar samples three to four billion years old, again congruent with our understanding of the extended geological evolution of the martian surface; crater density data suggested that ages of geological units on Mars spanned an estimated range from four billion to less than one billion years old. One rather unusual martian meteorite, ALH 84001, was found in Antarctica and determined to be relatively old: 4.5 billion years. Using a scanning electron microscope, tiny lifelike shapes were found inside the martian meteorite, forms resembling certain types of terrestrial bacteria, though much smaller and unique in detail. The authors of the ALH 84001 study suggested that these objects might be fossils of bacteria from an early epoch of Mars history. In other words, they asserted that traces of former extraterrestrial life had been discovered, a sensational claim that grabbed and held headlines.6

A flood of media coverage followed, eventually leading to press conferences at NASA Headquarters and finally, a Presidential Rose Garden statement. With that explosion of publicity, Dan Goldin moved to leverage some high-level political backing for a permanent, sustained Mars exploration program.7 Although human missions to Mars remained beyond the reach of technology, a series of robotic probes leading up to that elusive sample return mission would keep the Mars scientists and NASA’s Jet Propulsion Laboratory busy. “The Quest for Life” scientific gravy train was born.

By Saganizing the nation’s civil space program—that is, by enshrining the Quest for Life as NASA’s principal rationale for space exploration—Dan Goldin took the martian aspect of this new rationale and encapsulated it into the slogan, “Follow the Water.” The idea behind this messaging was that life as we know it requires the presence of liquid water.8 This dictum was followed by conducting a series of missions to areas on Mars where it was suspected that flowing water had occurred in the past. A cynical observer might notice that aside from the potential finding of extant or fossil martian life, no criteria for a programmatic exit from this exploratory path were defined. In essence, the new series of Mars missions took on a life of its own, becoming a permanent scientific and engineering entitlement program—a constant, uninterruptible cadence, elevated beyond the realm of peer-review selection pressure or second thoughts from planetary scientists, a situation viewed with dismay by the lunar community.

Despite the positive indications acquired from the Clementine and LP missions and subsequent studies of the presence of water ice and near-permanent sunlight near the poles of the Moon, NASA had no interest in conducting any follow-up investigations. Although these discoveries would permit long duration stays on the Moon and possible resources for additional spaceflight options, the lunar community could not get the funding to even study new missions that would have cost a small fraction of the JPL Mars program budget. Clearly, a policy decision had been made at some level that no large-scale human exploration program beyond LEO was possible: NASA’s robotic exploration budget was to be sequestered over the next couple of decades for various Mars missions. This policy was never formally written down, but as they say, money talks. Predominant in every submitted NASA budget for robotic science during the Clinton years were “green” spacecraft for Missions to Planet Earth and Mars orbiters and rovers. The former were the pet project of Vice President Al Gore, while the latter was the implementation of the wish lists of Dan Goldin, Carl Sagan, the Jet Propulsion Laboratory, and likeminded members of the Sagan-founded Planetary Society.

However, the Mars exploration program started running into some serious technical problems. After the renowned Pathfinder mission in 1997, the first successful mission to Mars since Viking two decades before, the next two Mars missions failed. The Mars Climate Orbiter, a 1999 mission designed to characterize atmospheric phenomena and look for possible clues to the record and mechanisms of climate change on the planet, missed its orbital insertion and was lost. Post-mission analysis traced this failure to the use of English units of measurement in a command stream that required metric units. Appropriate derision of JPL and agency competence followed this jaw-dropping revelation. Next, the Mars Polar Lander stopped transmitting shortly before its entry into the martian atmosphere; the inference is that it had crashed on the martian surface. Serious soul-searching at the agency followed these failures, but only about the means, not about the ends. One great concern was with Goldin’s alleged devotion to FBC (although it is hard to ascribe both of these lost missions to this paradigm, since their combined cost was over $300 million in FY1999 dollars) and not with the idea of a continuing series of Mars missions designed to follow the water. Following these failures, the revamping of the program now assured that the means of future missions to the red planet would each cost an appropriately staggering amount of money, all in pursuit of the elusive ends: water and therefore possibly past life.

The Human Space Program

Human spaceflight efforts following the demise of President George H. W. Bush’s Space Exploration Initiative (SEI) in 1992 included the continuation of the space shuttle program, with its wide variety of satellite deliveries and life science experiments, as well as servicing missions to the Hubble Space Telescope. The goal of building a permanently occupied human space station had not been abandoned, but it had been reimagined. Space station Freedom, initially proposed by President Ronald Reagan in 1984, went through several design iterations, changes that delayed the start of its construction and increased the cost of the program. Despite program review after the Challenger accident and the grounding of the shuttle fleet by hydrogen leaks, NASA pressed on with station design and redesign. The fits and starts of the program led to exasperation in Congress, where it survived a 1993 vote in the House of Representatives by a margin of one. The human spaceflight program had reached a crisis of both confidence and capability.

Despite the decline and termination of the SEI, debate continued over the future direction of human spaceflight, as outlined by the Paine, Ride, and Augustine 1990 reports. At this time, one of the biggest concerns of science and technology policy was the problem of nonproliferation. The Soviet Union had dissolved, and there were concerns in the West that Russian scientists might sell their services and capabilities to rogue nations to make the infamous “weapons of mass destruction” and cause the spread of nuclear capabilities. It was thought by some that a joint space project involving both the United States and Russia in collaboration would keep the Russian military industrial complex safely occupied and under the scrutiny of its Western partner nations. The Soviets had built a fairly large and capable space station in the 1980s called Mir. Soviet cosmonauts conducted routine, extended stays on Mir, arriving and returning on their Soyuz spacecraft. Announced in 1993, the logical, initial starting point for this new East-West spirit of cooperation, called Shuttle-Mir, had rotating crews taking the space shuttle to Mir, where crews would live together, showing that we could work together peacefully in space.9

Between 1995 and 1998, there were eleven shuttle missions to Mir, where American astronauts spent close to a thousand days in orbit aboard the Russian space station. Joint operational and flight techniques were developed between the two countries. Despite some shaky moments (including a fire onboard the station requiring quick and decisive action by the crew), both parties considered this cooperative flight experience successful, leading to the final redesign of the U.S. space station as a new International Space Station (ISS).10 This new design would be based on some key components provided by Russia. The Zarya (Functional Cargo Block), launched in 1998, and the Zvezda habitat and laboratory, launched in 2000, would become the nucleus of the new modular space station. Over the course of the next decade, twenty-seven shuttle flights and six Russian Proton and Soyuz flights would be needed to assemble the ISS in orbit. Starting in 2001, the ISS has been continuously occupied by crew, including during the period of the thirty months that the shuttle was grounded after the Columbia accident of 2003. With the delivery and attachment of the Alpha Magnetic Spectrometer, assembly of the ISS was finally completed in May 2011.

In the early years of the new millennium, as assembly of the ISS finally began, some in the agency considered the possible next steps for humans in space. Despite the failure of the SEI and the ongoing difficulties of the robotic Mars program, the obsession with human Mars missions was firmly entrenched within NASA. Most of the agency’s advanced planning people spent their time devising new architectures designed to achieve that elusive goal. A core group of engineers in the Exploration Program Office at the Johnson Space Center continued to evaluate the requirements and difficulties of a human Mars mission, as well as alternative concepts involving return to the Moon. The post-SEI analysis of the Houston engineers had determined that with the launch of a few large expendable rockets and a couple of shuttle flights, we could return humans to the Moon.11 Their analysis showed that the massive infrastructure creation outlined in the 90-Day Study was not strictly necessary, at least for the initial steps of human lunar return, especially if lunar resources (oxygen) were incorporated into the architecture. Such a mission would have limited stay time and capability, but at least it established a foothold on the lunar surface and could become a point from which the possibilities of extended presence could be investigated.

Studies of these architectures and plans continued, including investigations of missions to destinations other than the Moon. An early study mission favorite of NASA was the Lagrangian-point (L-point) mission, a human mission to one of the gravitational balance points in the Earth-Moon system, a point at which Earth and Moon appear to be stationary in the sky. The problem with L-point missions is that there is nothing there, except for what we put there. In the future, L-points could become critically important as staging areas for missions to the planets, or to collect exported material such as water launched from Earth or from the Moon. Although there was some interest in human missions to near-Earth asteroids, they were thought to be of much less importance, something to be reconsidered in the future. At the time, little was known about most of these objects, and asteroids had most of the disadvantages of a Mars mission (months of travel time, poor abort capability, and so on) with few of the benefits—for instance, most of these objects are simple, relatively homogeneous rocks, offering little in the way of exploratory variety.

As study of human Mars mission architectures continued, two things became increasingly clear. First, several technical developments, some of significant magnitude, were needed before human missions to the planet were feasible. Some of these involved “known unknowns,” things we know that we need but don’t yet have, like nuclear rocket propulsion or a solution to the dreaded entry, descent, and landing (EDL) problem,12 while others consisted of the “unknown unknowns,” problems of mission design or requirements that we don’t even know about, let alone have any idea how to solve. Given the state of our knowledge, these studies showed that a human Mars mission is not possible in the near future. Moreover, even at favorable opportunities, a Mars mission requires between one and two million pounds to low Earth orbit, most of which is propellant. It was estimated that to assemble in orbit a Mars spacecraft able to conduct a single human mission would require between eight and ten launches of a Saturn V-class heavy lift launch vehicle. The entire manned Apollo mission series of 1968-72 launched ten Saturn V rockets. This means that a single human Mars mission would cost several tens of billions of dollars, even if such a heavy lift vehicle existed. Other, more innovative approaches would have to be considered.

A key step toward understanding how to conduct a human interplanetary mission came in 1990 when Robert Zubrin, an engineer from Martin-Marietta, published his Mars Direct architecture.13 Although this plan bypassed the Moon, its significance for lunar exploration derives from its reliance on in situ resource utilization (ISRU). By manufacturing propellant on Mars for Earth-return—processing the carbon dioxide (CO2) in the martian atmosphere into methane (CH4) for propellant for the return trip—significant mass savings are realized, thus greatly reducing the initial mass required in LEO. In addition, the Mars Direct architecture separated cargo and crew. A nuclear power plant and the processing equipment needed to make methane propellant from the atmosphere would be delivered to the martian surface two years before the crew arrived. This approach introduced a safety factor, in that, if the atmosphere processing was less efficacious than believed, the crew would not be trapped on the surface of Mars without the fuel to get home because they would launch from Earth only after the return trip fuel had already been manufactured and stored on Mars. Despite these benefits, engineers from both NASA and the aerospace industry were slow to accept even the minimal risk introduced by the ISRU scheme proposed by Mars Direct. This ingrained resistance to ISRU carried over to architectures for lunar return as well.

Despite the innovative nature of some ideas in Mars Direct, a human Mars mission was still too high a fiscal and programmatic cliff to scale. Thus, for most of the 1990s, despite the presence of the alleged fossil forms in ALH84001 and Goldin’s lobbying, the Mars program remained a series of scientific robotic probes “following the water” while consuming more and more of the planetary exploration budget.

The Loss of Shuttle Columbia and Its Aftermath

In the years after Lunar Prospector, but before the Vision for Space Exploration (ca. 1998-2004), several attempts were made to restart lunar exploration, at least in terms of a series of robotic flights to address some of the new and exciting findings and unknowns about the poles. The vociferous debate over the presence and extent of polar ice continued and it was clear that more and higher quality data were needed to resolve the issue of water ice. Earth-based radio telescopes were barely able to see into parts of the permanently shadowed polar areas of the Moon. Both the eighty-meter Deep Space Network Goldstone and the huge, three-hundred-meter Arecibo radio dish mapped the south pole of the Moon, looking for evidence for the presence of ice. The data were inconclusive, since diffuse backscatter obtained solely from zero phase (monostatic) radar, in which the same antenna sends and receives the pulses, cannot uniquely distinguish between rock and ice. The bistatic technique, where the receiving antenna is different and separated by a known distance from the transmitter, can uniquely determine this, providing evidence that caused numerous scientists to support the interpretation that ice had been detected.14 As a believer in the polar ice hypothesis, I can attest to our desire to obtain new, high quality data from an orbiting radar experiment. The problem was finding a ride to the Moon. Japan has long harbored lunar dreams and had prepared a most ambitious orbiting mission, SELENE (later renamed Kaguya), a spacecraft the size of a school bus with a payload of almost every remote sensing instrument known to us.15 But SELENE kept getting delayed, then was grounded by a launch vehicle failure and a Japanese economy in recession. Europe kept studying lunar missions, including both orbiters and a south polar lander, but each time such a flight was proposed, it was deferred. After downsizing their lunar mission into a small, technology demonstration, Europe’s SMART-1 orbiter finally launched in late 2003, taking over a year to spiral out to the Moon using solar electric propulsion. The SMART-1 mission had limited instrumentation but it contributed to our knowledge of the poles by improving our mapping coverage and extending observation of polar lighting over a longer season.

A project sponsored by the Defense Advanced Research Projects Agency (DARPA) in 2003 looked at the possible impact of using lunar material resources to create new capabilities in space. This effort was mostly a paper study, although its authors hoped to parlay that report into a series of small robotic missions designed to follow up on the polar discoveries. I was working at the Johns Hopkins University Applied Physics Laboratory (APL), a university-based research organization similar to NASA JPL, when they studied that effort. We outlined concepts for a fleet of small satellites, each less than 100 kilograms, that could be operated in tandem to create high-resolution data on lunar polar environments and materials. Such a mission series would yield definitive answers for some polar questions, allowing us to understand if developing lunar water was feasible and what leverage in spacefaring capabilities it would yield. Although this topic is potentially the kind of transforming, “far out” idea DARPA claims to seek, the study was not approved to the next level of development, dashing the hopes of lunar enthusiasts yet again.

Despite its deferment, several positive results came from this effort. We understood how to configure a small mission that could get high quality data for the poles. A parametric study by a group at the Colorado School of Mines led by Mike Duke, former lunar sample curator and one of the masterminds of the 1980s lunar base movement, led us to understand the break points for lunar mining.16 For example, what concentration levels of water make the effort of lunar mining economically worthwhile? It turns out that water concentrations of at least 1 weight percent are needed to balance the estimated costs of extraction, including the transportation system. Fortunately, we already knew that the existence of such quantities was likely: LP hydrogen data indicated an average concentration of 1.5 weight percent for the entire polar region, suggesting the possibility of even larger amounts of water in the shadowed areas.

On February 1, 2003, the space shuttle Columbia broke apart during reentry.17 All seven crewmembers were killed. Until the cause of the accident could be determined and a fix applied, the shuttle would remain grounded. As with the loss of Challenger, the previous shuttle disaster in 1986, this accident once again focused the nation’s attention on the meaning and purpose of our national human spaceflight program. But this time, it did more than that. Sean O’Keefe, the new NASA administrator who had succeeded Dan Goldin in 2001, had a reputation as a “green-eyeshade” guy. He had been recruited to solve the agency’s considerable budgetary and accounting problems with the International Space Station project, which he did during his tenure of office. Profoundly shaken by the shuttle accident, O’Keefe decided that if humans were going to continue to risk their lives by going into space, there must be some great and meaningful purpose of national import to the trip.18 O’Keefe was determined to find it.

As most attention was directed to the Columbia accident investigation, a simultaneous and largely unnoticed parallel effort was undertaken to review the purpose and objectives of human spaceflight.19 It was recognized that future budgets for the civil space program were likely to be tightly constrained, so any possible plans must be constructed for an austere fiscal environment. Given these limitations, was there a way to revitalize the human spaceflight program, or had we reached the end of the trail?

Among those considering the next steps during this interruption in the human spaceflight program was Klaus Heiss, an economist who had conducted some of the early feasibility studies of the shuttle. He became convinced that a return to the Moon with the aim of learning how to establish permanence through the use of local resources could be achieved under current budgets, laying the groundwork for later, more ambitious space efforts. A friend of the Bush family, Klaus went directly to see the president with his idea, who passed it on to NASA for detailed technical study. At Headquarters, Associate Administrator for Human Spaceflight Bill Readdy and members his team undertook a feasibility study of Heiss’s plan for the establishment of a base on the Moon.20 The group continued to work on the problem of a return to the Moon for the next year and a half, coming up with an approach that was both affordable and technically robust.21 This “Gold Team” undertook an examination of the problem of trans-LEO human spaceflight, independent of previous advanced study work.

Over the remainder of 2003, a major cabinet-level study of the human spaceflight program was completed. The White House Office of Science and Technology Policy (OSTP), Office of Management and Budget (OMB), the National Security Council (NSC) and NASA all participated in this top-level review. Presidential Science Advisor John Marburger took an unusual and impressively independent path. Rather than rehashing the plans of previous “visionary” efforts and reports, he posed a fundamental question about human spaceflight: Why? What is our long-range purpose in space?

Many have wrestled with the “Why?” question over the years. Typically, this sort of pondering begins and ends in one’s own subdiscipline within the space business. For most of the scientific community, the answer has been to study the universe. For aerospace industrialists, it is to get long-term government contracts to build the biggest, most expensive machines ever imagined. For agency bureaucrats, it is to start, expand, and manage a large continuing program. Marburger reexamined the issue and posed a question: Why not bring space into our economic sphere? For years we have heard about “limits of growth” and various environmental crises, ironically enough, much of this talk spurred by the pictures of Earth taken from the Moon by the Apollo astronauts. But space contains virtually unlimited quantities of material and energy, and thus, in theory, unlimited wealth. Why not focus on developing the technology needed to harvest that wealth for the benefit of humanity?

While the public focused on the Columbia accident investigation, two competing streams of thought emerged.22 One, favored by OSTP and OMB, focused on the practical and economic aspects of the space program. Could we reorient and retool the program to become a creator, rather than a consumer, of wealth? To do that, we would need to learn the techniques of planetary resource utilization, habitation, and extended operations. During Apollo, we had visited the Moon briefly for the purpose of scientific study and exploration. To extract useful products from the materials found in space, we would need an extended presence and different types of equipment and operations. Given the new findings about the nature and potential of the lunar poles, the Moon quickly emerged as the initial destination for the civil space program beyond LEO.

The second stream of thought about future directions was a very familiar one to longtime space observers: a human mission to Mars, the project that many had long dreamed about. Once again, NASA hoped to emerge from the ashes of Columbia, Phoenix-like, to take humankind to the planets. It is fair to say that not all at the agency were on board with this direction—Readdy’s work on the lunar base studies, for example, showed considerable support for a return to the Moon—but it is equally fair to say that many were Mars-oriented, especially those involved in advanced planning decisions. A look through all the documents the agency produces detailing future missions shows that they largely revolve around the future, imagined needs of a humans-to-Mars program. Zubrin’s influence had infiltrated the agency enough to incorporate some of the features of his Mars Direct architecture, including ideas like splitting cargo and crew mission segments and ISRU propellant production. But no matter which way it was cut, a human mission to Mars was still too big a stretch, a much larger effort programmatically, technically, and fiscally than returning to the Moon. The battle lines were being drawn.

These behind-the-scenes events were largely unknown to me as 2003 wore on. Then a chance meeting occurred at a November gathering of lunar base advocates in Hawaii. At that gathering, I described results for the lighting conditions at the lunar poles and the evidence for water in the dark areas. Also in attendance was Indian scientist Narendra Bhandari, who described his country’s plans to fly its first mission to the Moon, the orbiter Chandrayaan-1. This small satellite was about the same size and capability as Clementine, and I felt an immediate affinity for their effort. During a break in the meeting, I approached Bhandari and asked him if they had considered flying imaging radar as part of the payload to map the dark areas near the poles. He replied that they had considered one, but imaging radars were too heavy and power-hungry and as such would not fit on a small spacecraft. I told Bhandari about our efforts to miniaturize a radar instrument for this purpose; we believed that we could make an imaging radar that would be less than 10 kilograms in mass and would use only 100 watts of power, an order of magnitude less than typical radar instruments. He promised to report our discussion to the Indian space agency and get back to me.

As the year waned, excited rumors circulated throughout the space community that a big announcement on space policy was imminent. The initial rumor held that President George W. Bush would unveil a new major space initiative in December, on the hundredth anniversary of the Wright Brothers’ first flight at Kitty Hawk.23 But that anniversary and celebration came and went without any announcement, causing some to believe that the policy plan was in trouble, when in fact it was merely in its final stages of review and briefing to Congressional and Executive personnel and staff. At a White House meeting in mid-December 2003, a final review of the new initiative was held. The idea was to announce the policy goal and then implement it, giving NASA a one-time budget augmentation of about $1 billion spread over the coming five years with the agency’s budget rising only with inflation in subsequent years. Because the shuttle was an expensive, labor-intensive vehicle, its operating costs constituted a large fraction of the total NASA budget. Results coming out of the Columbia Accident Investigation Board urged that the shuttle be retired. The new initiative slated the shuttle for retirement, to be replaced by a new, less expensive human space vehicle, the Crew Exploration Vehicle or CEV, with both form and specifications to be determined. This replacement spacecraft would consume less of the annual agency budget, creating a “wedge” of money saved from the shuttle program that could be spent on missions beyond low Earth orbit. Thus, from the very beginning of the new initiative, the agency was being challenged to approach the effort in a new and innovative way. This was not to be a typical new program, with automatic “plus-ups” to swell the budget, so much as a new strategic direction. Within broad boundaries, the agency was given latitude to pursue its new destination goals in the manner that it perceived best. But go where?

During the final review meeting, President Bush was presented with summary arguments for programs that focused on lunar return and human Mars missions. He recognized that the real objective was to create a new and bigger pie, not to simply decide how to cut and subdivide the remaining pieces of an existing, dwindling, small one. With its proximity and known resources, the Moon offered the possibility of early accomplishment, but more important, it offered a way to make an eventual Mars mission easier and more affordable. Thus, the president decided that the objectives were to be both Moon and Mars.24 In this sense, he was reinstating the goals of the abandoned Space Exploration Initiative that his father had proposed fifteen years previously. But this return to the Moon was different. In his major policy speech on the new Vision for Space Exploration (VSE), President Bush outlined the activities to be done on the Moon: to go there with the goals of staying for increasing periods of time to learn how to make useful products from what we found there. In other words, this lunar return was focused on sustained presence and the creation of new spaceflight capabilities.

Sustainability and the creation of new capabilities from what we find in space: these startlingly radical aspects of the new program were largely dismissed or ignored by many observers, who then went on to characterize the return to the Moon as merely the prelude to a human Mars mission. This false interpretation of the purpose behind the new policy was widespread within the agency, as well as in the space community as a whole. The confusion led to immediate and significant problems for many early strategic decisions on implementing the VSE. But when President Bush announced the new Vision on January 14, 2004, in a special speech at NASA Headquarters,25 space advocates were encouraged. Finally, a coherent direction had been imposed on what was widely perceived as a foundering, directionless program. Despite the expected carping from some in the space science sector, most agreed that the new strategic redirection of the civil space program was worthy. The president announced that he was forming a commission chaired by former Secretary of the Air Force Pete Aldridge to examine ways to implement the new Vision. This commission was to report back to him in six months. To my surprise, about two weeks after the announcement, I received a call from the White House asking me to serve on this commission, an assignment that I was more than happy to accept.

NASA now had a new direction and the possibility of a fresh start after the Columbia disaster. For lunar scientists and advocates, the new VSE was an intoxicating promise to revisit our object of desire, and to develop new technologies that would enable long-term human presence off-planet. For the Mars community, there was subdued rejoicing and a somewhat irritated acceptance of being relegated to a “long-term” objective. But as things progressed, we soon discovered that despite the clear strategic direction the VSE provided, following it was not going to be so easy.