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The solar wind implants gases into the lunar soil

While the resources of space have the potential to revolutionize spaceflight—giving us a much wider range of activities than are now possible, including habitation of other planetary bodies—discussions on various internet forums show that there is a lot of confusion and lack of knowledge about space resources in general and lunar resources in particular.  To some, the idea of harvesting and using resources from a body other than Earth has a science-fiction aura—for them, air, propellant and food manufactured for people belongs on the silver screen, not in space or on other worlds.

So, what is a “space resource?”  In broad terms it is needed materials or energy derived from space itself.  The value of space resources is immediately obvious; at transport and delivery costs exceeding $20,000 per pound to low Earth orbit, everything we find and use in space is one more thing we do not have to pay exorbitant costs to transport.  For human spaceflight, consumables are heavy but absolutely necessary.  This category includes air, water, electrical power, and rocket propellant.  On a long space journey, we could save millions to billions of dollars by re-fitting consumables in space rather than dragging them all up to orbit with us from the deep gravity well of the Earth.

Unfortunately, the materials and energy we need in space are not there in the form we need them.  Thus, our task is to convert what we find into what we want.  There’s nothing magical about this – modern industrial chemistry is largely concerned with this very topic.  All you need to convert chemical substances in one form to another one is time and energy.  Fortunately, both are available in quantity in space, especially if you use automation and robotics to perform a lot of this work.  Creating systems to harvest and utilize space resources has the benefit of boot-strapping a self-sustaining, spacefaring capability instead of remaining tethered to never-ending, one-off expenditures and Earth’s gravity well.

For many years we have used energy provided by the sun to generate electrical power in space but we have yet to use any material resources.  The Moon is the nearest object offering usable resources.  Contrary to common belief, the lunar surface contains virtually all the elements one needs to create usable products for human space faring, including air, water and rocket propellant.

It’s often said that the Moon is resource-poor.  That is inaccurate; the Moon is resource different.  It is depleted in volatile substances (those that have very low melting points).  The most important rare resource on the Moon is hydrogen.  The Moon itself has very little of this element, but the soils have a great deal of it; because the Moon has no atmosphere or global magnetic field, the stream of protons from the Sun (the solar wind) implants hydrogen onto the surface of the dust grains on the Moon.  This solar wind hydrogen can be released through heating of the dust.  When you have both hydrogen and oxygen, you have air, water, and rocket propellant.

The typical hydrogen concentration in most soils is 20 to 100 parts per million.  This is enough quantity to extract and use, especially if much of the mining and processing work is done through robotic machines operated from Earth.  Hydrogen appears to be present in higher quantities in soils that have high titanium content, which are abundant on the lunar near side (the Apollo 11 landing site has one of the highest titanium contents found on the Moon to date).

Now there are even more exciting resource prospects.  The Moon has abundant hydrogen at the poles, enriched by more than a factor of three over the global average.  Some of this hydrogen, present in the permanently dark and cold floors of polar craters, may be in the form of water ice.  Additionally, with the spin axis of the Moon perpendicular to the plane of its orbit around the Sun, some peaks near the poles appear to be in near-permanent sunlight, permitting continuous collection and use of solar electrical power, as well as the important benefit of a near constant surface temperature.

For these reasons, recent international exploration of the Moon has focused on the poles of the Moon, where extracting and using lunar resources is easiest and where humans have the greatest potential to learn how to live off-planet and exploit space resources to create routine access in cislunar space and into the Solar System.

Next: Changing our approach to spaceflight.

Earth set over the south pole of the Moon, seen from the Kaguya orbiter

A newly formed commission led by Norman Augustine will review NASA’s human spaceflight program with the aim of determining if we are on the “right track.” This is familiar territory for Augustine, who led the 1990 Advisory Committee on the Future of the US Space Program. Now, 19 years later, it may seem that he’s treading across similar ground, but the landscape has changed.

Compiled in the wake of the Challenger accident, the first loss of an American crew in flight, the Commission was charged to consider 1) Should America have a human space program; and 2) if yes, what should be its goals? The 1990 report concluded that human spaceflight was an essential part of the program and that the long-term goal of human exploration is Mars, preceded by a LEO Space Station which emphasizes life-sciences and microgravity research, an exploration base on the Moon, and robotic precursors to the Moon and Mars (Recommendations 4-7). The view of the Moon in Augustine 1990 was to explore the Moon as a test-bed for future missions to Mars. The report emphasized that the lunar base was to be built such that it could be human-tended, but not require permanent staffing. Surface activities were worded carefully because as far as it was known in 1990, the Moon offered little or nothing to sustain a long-term human presence.

Sustainability on the Moon revolves around two principal issues: power and consumables. Destinations in space typically lack one or both of these vital commodities. That’s why we bring all our consumables ( air, water, rocket propellant and electrical power) with us. For some time now, we’ve been able to generate electrical power in space using solar arrays, but these have the drawback of being unusable during night and periods of eclipse.

The Moon was viewed as a barren desert. True, it has no atmosphere or flowing water. Lunar samples are exceedingly dry and contain no water-bearing minerals. Moreover, the Moon has a slow rotation rate (28 days), meaning that after a scorching 14 Earth days in sunlight, you freeze for 14 days of cold, no-solar-power nights. These properties led to a concept of operations that emphasized transient stays on the Moon, science exploration and use of the Moon as a test-bed for Mars.

However, in the intervening twenty years since that Augustine report, several robotic missions have changed the way we perceive the Moon. We found that the poles are very different from the rest of the Moon. The 1994 Clementine mission found large areas in permanent shadow near both poles; the sun never reaches the bottoms of craters here because Moon’s spin axis is almost perpendicular to the plane of Earth’s orbit around the Sun (the ecliptic). Such areas are extremely cold, possibly only a few tens of degrees above absolute zero. Water added to the Moon through bombardment by water-bearing meteorites and comets for billions of years could be retained in these dark areas. Additionally, we found areas in close proximity to these dark regions on mountain peaks rising above the local horizon that are nearly continuously illuminated by the Sun. In 1998, the Lunar Prospector mission found elevated amounts of hydrogen in the polar regions, consistent with the accumulation of excess volatiles (including water).

So what do these discoveries mean for lunar return? We now know that sustained human presence on the Moon is possible, largely because we’ve found a source of near-constant power (permanent sunlight) and a source of sustenance and rocket propellant (volatiles, including water). The robotic Clementine and Lunar Prospector missions showed us that the poles, almost completely unknown in 1990, are inviting oases on the lunar desert. There, we can extract hydrogen and oxygen to make air and water for life support and propellant to fuel rockets. The sunlit areas can generate near continuous electrical power, with regenerative fuel cells providing power for the short duration eclipse periods. Locally obtained power and consumables means that continuous human presence is possible, without the enormous expense or unproven technology of large nuclear reactors and the delivery of massive quantities of material from Earth.

The new Augustine committee should be made cognizant of these facts. The more we learn about the true nature of the Moon, the more the goal of learning to live there on a quasi-self sufficient basis appears feasible. This opens up wholly new areas of operations and commerce in space, undreamed of as little as twenty years ago. It has the potential to change the entire paradigm of spaceflight, from a narrow, government-run, science-oriented program, completely dependent upon the caprice Congressional largess to a self-sustaining, free-market program, in which NASA develops and demonstrates new technologies that open up spacefaring by many different passengers and payloads for a wide variety of purposes.

Much of the original 1990 Augustine report is directly applicable to today, including a gradual movement of humans beyond LEO and a “go-as-you-pay” paradigm for agency funding. By using the Moon, where expanded dimensions in exploration can be developed and tested, we will transform and enhance the business of spaceflight.

Outpost on the Moon: Too expensive?

Recently, the acting Administrator of NASA testified before Congress on his agency’s implementation of our National Space Policy, previously known as the Vision for Space Exploration (VSE).  In the question and answer period, he made a rather startling statement to the effect NASA was still trying to understand what “lunar return” means – that an outpost would be “expensive” and that lunar return might instead entail a series of smaller scale sortie missions, similar to the later Apollo expeditions of the early 1970’s.  He added that people should remember that the “original purpose” of the VSE was to prepare to go to Mars and other destinations.

I found this exchange fascinating because it suggests that NASA, as an executing entity, still doesn’t fully understand the nature of their mission to the Moon and to the extent that it is understood, they have transformed it into something very different from what the VSE actually said and what was intended.

To begin with, what did the Vision actually say about lunar return?  The Vision consisted of both documents and speeches (all linked on this page) that included the following points:

1. The purpose of the VSE is to serve national scientific, security and economic interests.
2. The Moon is a source of material and energy resources that we can access and use to create new spacefaring capability.
3. We return to the Moon to explore it scientifically, to learn how to live and work on another world and how to extract and use lunar resources.
4. This experience on the Moon will allow us to journey beyond the Earth-Moon system, first to Mars and then to other destinations.
5. We undertake this journey with small, incremental, cumulative steps, all designed to fit under NASA’s current budgetary envelope.

Apparently, the view of NASA’s acting Administrator is that the Moon is a box to be checked-off on the way to Mars.  Hence, we don’t really need to establish an outpost because we’re just satisfying a political requirement in implementing policy, not conducting a technical experiment to use the Moon to prepare for journeys beyond.

Why is an outpost on the Moon necessary?  Or more pressingly, why are sortie missions undesirable?  Each time you go to the Moon, launch and spacecraft assets (in the form of equipment and vehicles) are expended.  This equipment has significant cost; it is currently estimated that a single Orion sortie mission to the Moon might cost upwards of $ 4-5 billion dollars.  A sortie mission goes to a single, specially designated landing site,  the crew explores the local area, sets up some experiments and then departs.  All equipment brought to the Moon is abandoned.  Thus, a sortie mission’s high costs are pure expenditure, not investment.  The return from sortie missions is scientific knowledge, something which as a lunar scientist, I certainly desire.  But a sortie mission does little to advance the goals of learning how to live on another world or for extracting and using local resources, except for relatively short duration stays and technology demonstrations.

In contrast, an outpost at a single, optimally placed location can be built up from delivered hardware as each flight incrementally adds some equipment or facility.  Thus, the cumulative capability of the outpost increases with time.  This seems fairly obvious and in fact, has been recognized for many years; Arthur C. Clarke’s classic book The Exploration of Space (1951) notes:

For a considerable time all flights to the Moon would be directed to the same spot, so that material and stores could be accumulated where they would be most effective.  There would be no scattering of resources over the Moon’s twelve million square miles of surface – an area almost exactly the same as that of Africa.

An outpost allows infrastructure to be built up rapidly and over the long run, permits and enables more exploration than a series of sortie missions.  In other words, you build up capability on the Moon first, then stage the sortie missions from the Moon rather than from the Earth.  Ultimately, this permits longer and more capable exploration than would otherwise be possible.  The idea that an outpost is “more expensive” than sortie missions is ludicrous; an outpost can be built at any rate that budgetary limits permit.  And it represents more value for expenditure because equipment gets re-used or at a minimum, used once to the maximum extent possible.

Much of this is so obvious as to be beyond debate.  Could the agency’s focus on sortie missions be because those implementing the program don’t believe in the primary mission, which is to use the Moon to learn how to live off planet?  Do they think it unlikely that this will be possible or do they believe that activities on the Moon will “bog them down?”  Is the strategy to advocate short duration sortie missions to “get data” and conduct their experiments before ending the program?   The Vision’s purpose is clear, so one must conclude that they are eager to “check off the box” for the Moon and get to their mission of going to Mars.  To do that, the first three parts of the VSE must be curtailed.  As others have pointed out, the Constellation program is not optimized for the establishment of an outpost on the Moon.

A return to the Moon using the Apollo exploratory template is truly a “been there, done that” exercise in space futility.  The Vision was never intended to be a repeat of Apollo – the idea was to use the Moon to create new spacefaring capabilities.  This is a task that’s never even been attempted in space, let alone accomplished.  It is the antithesis of “been there, done that.”

It appears that some at NASA have been successful in obfuscating the purpose of the Vision.