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Return to the Moon

apsmith writes "No matter what the subject, one has to admire a book written by an astronaut and former US senator, illustrated with photos of the author at work on the Moon. When the subject is one as potentially important to the future of our civilization as the energy resources geologist Harrison ("Jack") Schmitt sees buried in the lunar surface, along with our future in space, it becomes all the more daunting to take issue with it. Unfortunately Schmitt's potentially inspiring commercial justification in Return to the Moon: Exploration, Enterprise, and Energy in the Human Settlement of Space rests on a shaky foundation." Read the rest of Arthur's review. Return to the Moon: Exploration, Enterprise, and Energy in the Human Settlement of Space author Harrison Schmitt pages 336 publisher Praxis Publishing Ltd. and Copernicus Books rating 7 reviewer Arthur Smith ISBN 0387242856 summary Harvesting Helium-3 from the Moon

With NASA now planning a lunar return and several other countries planning missions, the time is certainly ripe for a book titled Return to the Moon. In fact, last November also saw the release of Rick Tumlinson's collection of essays from experts on the subject with the same title, and the Space Frontier Foundation has been running regular Return to the Moon conferences.

Schmitt's book acknowledges that context but sets out in his own direction arguing that the Moon will provide a critical contribution to our civilization's energy needs, and the lunar return discussed is primarily one of industry and commerce, rather than grand national programs. The argument for industrial use of our celestial neighbor hinges on the utility of helium-3 fusion. However, that technology and the science behind it is dealt with in a perfunctory 4 pages in this book; Schmitt leaves the main argument to scientific papers from the University of Wisconsin Fusion technology Institute that has been promoting it.

Helium-3 fusion, while having the advantage of lower radiation levels, is considerably harder than deuterium-tritium (D-T) fusion: the extra proton in helium means the ideal fusion temperature for He3-D mixtures is over four times as large. An alternative hydrogen-boron reaction would require almost 10 times the D-T temperature. That makes the traditional approaches to fusion reactors, creating very hot and dense plasmas, essentially impractical for He3 fusion. Non-traditional electrostatic confinement ( "Farnsworth fusor") technology gets around the high temperature problem by essentially shooting the nuclei directly at one another in a steady-state fashion. In principle any kind of fusion is possible with such a design. However, in practice the maximum power output obtained so far is 1 Watt - you would need a hundred of them just to power a light bulb!

So that leaves a huge and unknown technology gap in scaling things a factor of 1 billion or so to power plant size. Schmitt lightly skips over this problem with the note that "much engineering research lies ahead" and then bases an economic analysis on the assumption that such a plant would have to compete with fossil-fuel plants; we know roughly the numbers there. This does provide real constraints on the costs of retrieval of He3 from the Moon, so it's a useful analysis. But there's still the fundamental question of whether He3 fusion could ever be economically practical.

Schmitt doesn't let those questions slow him down; cost estimates for the "much engineering research" piece are folded into capital cost estimates for building up to 15 fusion plants, building and launching (and staffing) 15 lunar mining settlements, and operational costs for the whole system to reach the conclusion that it could, after the 15th set of facilities was completed, be close to competitive with electric energy from coal. That's not a bad accomplishment, but it rests on a lot of assumptions of unstated but likely very high uncertainty.

Ironically, the best reason for replacing coal, the threat of global warming from atmospheric CO2 release, is given short shrift as an "international political issue" in Schmitt's introductory chapter on our energy future. In this and in a bias toward non-governmental solutions, Schmitt's text unfortunately betrays the caution of an incompletely recovered politician.

Organizational approaches are covered in detail in chapter 8, where Schmitt compares models ranging from all-government to various public/private partnerships, to an all-private approach, analyzing each model according to over two dozen financial, managerial, and external criteria. After giving each a 1 to 10 rating, he multiplies by another subjective weighting factor and adds them all up. Somehow, the all-private model wins every time. The text surrounding these numbers suggests that, despite what the numbers say, several of the public-private partnership approaches make a great deal of sense. This ranges from the Intelsat multilateral model to simply encouraging government funding of the necessary research, development, and testing, and passing technology on to private industry to earn a profit.

Schmitt's discussion of lessons from Apollo is almost reverential, including a proposal for a "Saturn VI" heavy-lift rocket, to lower launch costs. It seems unlikely that the Apollo conditions can be duplicated, but he does have an interesting argument in favor of in-house engineering talent and having a large pool of young engineers. This and the letters of chapter 10 are perhaps too bluntly put to have an impact on NASA directly, but could certainly help inspire organizational virtues in a private venture, so NASA's more recent mistakes aren't repeated.

There is much that is good here. The book covers some ideas in detail, including the lunar geology issues for helium-3 recovery. Designs for mining equipment, the idea of finding markets first in space, and only later on Earth, and the proposal to make the miners permanent settlers, rather than just temporary visitors are all interesting concepts developed here. The author has included copious citations for more in-depth reading.

Much of the infrastructure Schmitt calls for could be applied to any other commercial utilization of the Moon, for example to help develop solar power satellites or lunar solar power facilities, to provide lunar oxygen (or hydrogen) for in-space use, for lunar tourism, and so forth. Schmitt believes the He3 approach provides easier access to capital markets due to lower start-up costs, so less government involvement may be needed than for those other commercial justifications for a lunar return. However, the status of He3 fusion itself seems sufficiently uncertain that relying on private equity to make it happen could still be a very slow process, at least once development reaches the point of billion-dollar space missions.

This vision for a new day in lunar exploration is very different from what we have been hearing from NASA, even in recent years when a human lunar return has been on the table. There is considerable evidence we have an urgent need for new energy sources. The possibility of exploitation of the Moon for human benefit has hardly crossed public consciousness yet, but it's something that we will increasingly be turning to as humanity reaches limits here on Earth. We should all be grateful Dr. Schmitt has helped here to get that ball rolling.

Arthur Smith is a part-time space advocate and volunteer with the National Space Society."

You can purchase Return to the Moon: Exploration, Enterprise, and Energy in the Human Settlement of Space from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.

3 of 197 comments (clear)

  1. Re:What about conventional fission reactors? by Rei · · Score: 5, Informative

    The article review was rather poor. There are three points that need clarification.

    1) Electrostatic confinement is hardly the only fusion method that could possibly scale to second generation nuclear fuels; discussing only magnetic and electrostatic confinement leaves off the whole range of potential fusors.

    2) Farnsworth fusors are inertial electrostatic confinement, not electrostatic confinement.

    3) The problem with inertial electrostatic confinement is the same as with most methods of fusion currently: it takes far more energy going in than comes out (not all methods - we've had energy output surpass energy input in magnetic confinement fusion, although it's not breakeven). The problem is not its scale; higher power Farnsworth fusors could easily be built.

    4) The serious issue that the writeup omitted is the fact that we can make He3 right here on Earth. Neutron bombardment of lithium targets can produce tritium, which can decay to He3. We just need to increase production of tritium in our reactors.

    --
    I just invaded Grammar Czechoslovakia and duped Grammar Neville Chamberlain; now it's on to Grammar Poland.
  2. Re:Think about it by Shihar · · Score: 5, Insightful

    While it is true that the Earth is going to end at some point, that ISN'T a reason to go the moon right now. Right now, to get to the moon and do anything is massively expensive. The cost associated with actual colonization is mind blowing. Why do it RIGHT NOW, when there is no pressing need? Why not let technology further improve and refine before spending the many billions or trillions of dollars it will take to do something of substance on the moon?

    Going to the moon now would be like building a 100 story sky scrapper in 1880. We probably had the technology back then to brute force our way around the problem of supporting such a massive structure. We could have mustered the man power to build it. It just would have consumed a noticeable portion of the GDP for minimal benefit. We didn't build such a structure though; we waited 50 years and got the Empire State Building. The Empire State Building was cheaper, safer, and more effective at what it did then the solution we could have kludged together 50 years earlier. Going to the moon now instead of waiting 50 years is no different.

  3. Pebble Bed Reactors are a Scam by mosb1000 · · Score: 5, Informative

    Pebble bed reactors offer few, if any advantages over conventional light water reactors. They are safer than old-fasioned reactors, but Generation IV light water reactors would probably be just as safe. Likely they would be more safe because we know more about them from past experience.

    Also, it has now been shown that it may be possible to make LWR breeders, which would pretty much solve or energy problems for the foreseeable future.

    There is no good reason to waste money on pebble bed reactors when existing solutions are probably superior. If you want to advocate research into obscure reactor designs, you should look into molten salt reactors. The lack of fuel elements makes fuel reprocessing more economically feasible, which may mean reduced waste disposal costs, as well as cheeper breeder reactor alternatives.

    You may also wish to look into liquid metal fast reactors, which have a breeding ratio so high that they guarantee a long term supply of future energy. These haven't taken off because of the costs of reprocessing fuel (and the relatively low cost of uranium) but they're much more interesting and potentially beneficial than gas cooled reactors like pebble bed reactors.