Dr. Paul Spudis, most recently from the Lunar and Planetary Institute, paid a visit to Marshall Space Flight Center yesterday and gave a lunch-and-learn presentation entitled "Using the Resources of the Moon to Create a Permanent Cislunar Transportation System." This was the sort of talk that one normally hears at an International Space Development Conference or other space advocacy event. It contained everything a space advocate could hope to hear: technical feasibility, visionary ambition, and a sense of political realism. It's been awhile since I've heard such talks--I was working during most of my ISDC--and it was a pleasure to hear Dr. Spudis's speech. Nevertheless, I had a few reservations, which I'll share after I summarize the talk.
Spudis began his talk by providing some background on the space industry, specifically its three "ages," the "Space Race" age (1957-1972), the "What now?" age (1972-Present), the "Beyond LEO" age (hopefully, from now into the future). He made the case early in his talk that if we lack an overarching beat-the-other-guys reason for space exploration, we need to find more pragmatic reasons, including national security, economic, and scientific, all of which space justifies in spades.
He next went on to discuss the operational challenges space efforts have faced, including a long habit of building customized, one-time-use platforms, which are then abandoned after one use. Spudis argues for a new template for human space activities, one involving incremental, extensible building-block components and systems that can be reused. He also argued (as his title suggested) for the use of space resources--but not for use here on Earth, but rather in space.
Another template or paradigm Spudis asked the audience to consider was a shift from an "Space Air Force" model, where there are small vehicles and small-scale, temporary visits to destinations to a "Space Navy" model where you see a large-scale, permanent presence in space and at destinations. It's sort of like the difference between The Right Stuff and Star Trek. However, instead of Star Trek, Spudis pointed to Arthur C. Clarke's Profiles of the Future.
It didn't surprise the audience that Spudis, a lunar scientist, advocated for using the moon as a base of operations and resources. As his PowerPoint bullets put it, the moon is "close, interesting, and useful." He got a little incensed by President Obama dismissing the moon with "been there, done that." Citing recent discoveries by the Lunar Reconnaissance Orbiter (LRO) and Lunar Crater Observation Sensing Satellite (LCROSS), Spudis emphasized the usefulness of lunar resources, including local metals and most importantly water ice. For those unschooled in the matter, scientists have determined that under the rims of craters near the moon's north and south poles there are permanently shadowed areas where volatile materials such as water would not be able to boil off. This water, in the form of ice, comprises as much as 10 percent of lunar soil in these regions.
Water, as Spudis points out, is just about the most useful material available for human space exploration, as it can be used to drink, it can be split into hydrogen and oxygen for fuel, it can be used to provide oxygen for breathing, and it can be used as an insulating material for surface habitats. In short, water matters, and where we once thought the moon was bone-dry, we now know that there's enough water ice there to meet the needs of human settlements there for hundreds of years.
Having set the stage for "why the moon," Spudis next moved on to his architecture, which was developed in cooperation with Marshall Space Flight Center project manager Tony Lavoie. This incremental set of hardware includes (in order) communication and navigation satellites, polar prospecting rovers, in situ resource utilization (ISRU) demonstrator, digger/hauler rovers, water tankers, electrolysis units (for transforming water into hydrogen and oxygen), supporting equipment, and space-based assets, such as fuel depots in lunar and Earth orbit. Total price tag, about $5.5 billion per year for 16 years. That's an easier figure for Congress to swallow than the total pricetag, $88 billion, but it's MUCH easier than the $450 billion estimated for the Space Exploration Initiative, proposed by President George H. W. Bush in 1989.
The Spudis/Lavoie approach has several advantages:
- It is "vehicle neutral," meaning it is not dependent on any new or existing rockets to get its equipment into space (they start with the existing Delta IV as their baseline, but any existing rocket would do.
- Because the early missions--heck, the first 16--are robotically based, they can be developed more quickly, on shorter timelines than human missions. Multiple, short-term milestones and accomplishments are important because Congress runs its budgets one year to the next and is impatient with programs that they feel are not accomplishing anything.
- It allows transportation to be customized by function, much as Robert A. Heinlein envisioned it: Earth to LEO handled by one type of vehicle, LEO to the moon with another type of vehicle, and a reusable vehicle of another type to handle the lunar orbit to Moon run.
- It can identify an economic "break-even" point. In the case of water resources, any surplus above 150 metric tons of water extracted from the moon would be sufficient for a lunar settlement to start paying for itself.
And I should point out that this is very much a NASA type of vision, with the agency leading the activities. Why? Spudis's thoughts are much like mine on this: there is very little business justification for exploring the moon or building infrastructure. Basically, if this vision/architecture were left to the private sector, "it wouldn't happen." So another advantage of Spudis's architecture is that it concentrates government on activities that are unlikely to generate much initial commercial interest.
It sounds like a cool, ingenious plan. But then so do a lot of the plans I've heard from the space advocacy community over the past 15 years. My comment (one seconded by Michael Doornbos when I mentioned the talk on Facebook) was, "All they need is an affordable launch vehicle." Other plans are equally ingenious, but they always have some missing unobtainium that hasn't been developed yet. All our problems would be solved if only we had...
- An affordable launch vehicle
- A reusable launch vehicle
- An ultra-light alloy that would make a reusable launch vehicle possible
- A new, high-energy propellant
- A new, high-strength material capable of building a space elevator
- A space station orbiting at the L5 Lagrange point
- A base on Mars
- Access to a nickel-iron asteroid with a trillion dollars' worth of platinum-group metals
- A Helium-3 reactor
- The political will to do [X]
- A heavy-lift launch vehicle
- A robust, low-cost commercial space industry