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Moon Books Media Space Book Reviews

Return to the Moon 197

Posted by samzenpus from the we've-come-for-your-he3 dept.
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.
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Return to the Moon

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  • What about conventional fission reactors? (Score:4, Insightful)

    by PIPBoy3000 ( 619296 ) on Friday January 13, 2006 @01:57PM (#14465653)
    Basing policy on technology that doesn't exist seems rather silly at this point.

    If the energy crisis is so severe, why isn't America investing in things like pebble bed reactors? [wikipedia.org] With the Iraq war potentially costing $2 trillion dollars [guardian.co.uk], that's a lot of money that could be invested in alternative energy sources.
    • pebble bed reactors arn't really any more energy efficient getting any new reactors up would be a good thing.

    • Re:What about conventional fission reactors? (Score:5, Informative)

      by Rei ( 128717 ) on Friday January 13, 2006 @02:11PM (#14465784) Homepage
      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.
      • Also apparently needing clarification: the number three is now equal to the number four.
      • The only point of using He3 as a fusion fuel is to reduce neutron production and the consequent radiation hazards. If you're creating He3 using vast streams of fission reactor neutrons, for instance, you're depending on something that Schmitt would like to eliminate.

        Not that I think radiation is that much of a problem that it requires this, but there is a rational argument in Schmitt's approach.

        Now, would you mind explaining what other "whole range of potential fusors" I omitted in the review? I actually di
        • But He3 produces neutron streams as well though - just not as intense. For example, lets say you want the aneutronic D+He3->He4 (3.6MeV)+p (14.7 MeV) reaction. Well that's all nice and good, but what's to stop D+D fusion, which is much easier? Nothing. Even if you run Dt lean, it will still happen a'plenty. What about He3+He3? What about impurities, such as H and T? What about reactions involving the He4, or some of the neutrons that we're getting, and the products generated from *those* interacti
      • Oh, on point 3 - yes of course at the 1 Watt scale you're putting in a lot more energy than you're getting out. The first step for any energy source is of course to get to the point of positive energy return - but the real point you need to get to is positive economic return; in principle both should come from scaling the technology up to large enough sizes - that is, if the technology even has any potential for positive energy return in the first place. Which IEC fusion may not - sorry if I didn't make tha
    • Oh, and I'm quite glad we're not investing in PBMRs. There are much better next generation fission reactor designs, such as lead-bismuth breeders. I'll pass on a reactor that uses graphite as a moderator and has no containment structure, thank you very much.
    • >Basing policy on technology that doesn't exist seems rather silly at this point.

      Ironic for you to say such, considering it was posted in a thread on going to the moon. The technology to send a man to the moon and return him safely to the Earth existed only on paper when Kennedy committed the country to the goal of going there before 1/1/70.

    • Pebble Bed Reactors are a Scam (Score:5, Informative)

      by mosb1000 ( 710161 ) <mosb1000@mac.com> on Friday January 13, 2006 @02:24PM (#14465934)
      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.
      • No, PRB's have one big advantage....

        They have better energy density than RTG's but the same degree of safety (i.e. as long as you don't crack the casing, it's safe)

        But, yes, there's a ton of neat reactor designs that should make nuclear weapon production harder, increase safety, etc.
      • Reactors use fuel to heat water to drive steam driven turbine generators right.

        How much heat is needed? How many turbines are there? Could we not instead of using uranium, rather
        use photos to heat the water from the sun, fed by giant lenses fed by fibre optics, so we could in effect
        have lots of collectors 10m wide funnel the light down 1inch fibres all heating the water pipes
        which drive the turbines. Sure its only during sunlight, but damn, its 100% free once running. Even during
        cloudy days, but not real re
    • Unless its found there (on The Moon), it is really expensive to ship it there. So sending millions of tons of coal and oxygen (remember you need to *burn* it) to The Moon is not economically reasonable. There is also the problem that a coal fire power plant on The Moon have to function differently than one on Earth .

      So you are quite right: Going with technology of today a fission pebble bed reactor makes a lot of sense. The only way to get better and safer reactors is to build and learn from designs. B
    • I respectfully disagree with your opening statement (taking it at face value). If our lawmakers and corporate honchos had used some foresight to base policy upon emerging (or future) technologies, we may not have all the legal problems we've had with things like DMCA, DRM, SPAM, etc.
    • Lets asume that if the iraq war wasn't going on, the money being spent would actualy be used for somethign else like energy research. Why wouldn't be a good policy to bank on technoligy that doesn't exist. Sure it won't be realized anytime soon but the advancments could lead into other areas of eficciency as well as benefiting all of mankind. The space program while credited by some for inventing more things then it actualy had did invent alternative uses for these inventions that lead to thier wide spread
    • This is W's America! We base ALL policy on technology that doesn't exist! We have a missile defense system, abrogating a perfectly good treaty, based on nonexistent technology to counter nonexistent technology. We went to war in Iraq to counter nonexistent WMD technology. Our current rationale for going to the moon is to refuel for a mars trip, which would better achieved in low earth orbit.

      In that context, going to the moon for He-3 is too realistic to get support in this administration!

  • Think about it (Score:4, Insightful)

    by somethingprolific ( 944769 ) on Friday January 13, 2006 @01:59PM (#14465671)
    I know this sometimes seems silly but we need to invest in any projects that lead to plausable human habitation of the moon. Whether it be for resources or for recreation. Earth will NOT be here forever and any steps we can do to begin the transition of being less reliant on the Earth's resources the better off the human race will be in the long run.

    • Re:Think about it (Score:5, Insightful)

      by Eightyford ( 893696 ) on Friday January 13, 2006 @02:08PM (#14465752) Homepage
      I know this sometimes seems silly but we need to invest in any projects that lead to plausable human habitation of the moon. Whether it be for resources or for recreation. Earth will NOT be here forever and any steps we can do to begin the transition of being less reliant on the Earth's resources the better off the human race will be in the long run.

      Well the Earth will be here for a few billion years. That's a long time, you know. And, even if all of the nuclear weapons that ever existed were detonated right now, the Earth would still be a hell of a lot more habitable than the moon.
    • >Earth will NOT be here forever and any step

      Humm... If we had to move I'd rather to somewhere more hospitable than Earth, rather than less.

      The alternative of course would be to send the worst polluters to the moon, thus delay the date when the rest of us need to move off!

      • If we had to move I'd rather to somewhere more hospitable than Earth, rather than less.

        Won't happen, our bodies are designed specifically to live here. And even if we figure out something like terraforming, it will be easier to use those techniques to tweak earth a little bit than to turn a lifeless dusty rock into the garden of eden.

        I'm not saying we won't colonize, but I think Earth will always (i.e. for a long long time) be the prime real estate for humans, unless we wreck it.

    • Re:Think about it (Score:5, Insightful)

      by Shihar ( 153932 ) on Friday January 13, 2006 @02:22PM (#14465908)
      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.

      • Re:Think about it (Score:3, Insightful)

        by Anonymous Coward

        Technology only progress's when there is a need for it to progress. If we sit and wait, the technology will not become more advanced, since there won't be a need for it to. If we do go back to the moon NOW, it will help progress technology to make travel to and from the moon cheaper in time.

        I don't understand why people would think that technology will progress 'magically' by just sitting around waiting for it too.

        • Re:Think about it (Score:2, Informative)

          by Punchcardz ( 598335 )
          There have been many advances not related to space exploration that will make future exploration easier. Better computers, lots of work in material sciences, biotechnology, etc. all can be applied to making space exploration more feasible, and are continuing to progress without an intensive manned program. Have some advances in those fields been driven by the space program? A bit. But to claim that no progress will take place without an agressive program is silly. I'm all for expanding to the stars. Going
      • This is a stupid analogy. We went to the moon 36+ years ago already.

      • Why do it RIGHT NOW, when there is no pressing need?

        Gee, because maybe by the time there is a pressing need -- say, a giant extinction-causing asteroid six months away from ramming into Earth at 25,000mph -- there won't be time to develop a whole recolonization program from scratch. And if you discount developing colonization programs, you're also killing off propulsion research that might be beneficial in developing a rocket that could deflect said asteroid. This is just one of several examples I could
      • 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?

        There is a pressing need. The destructive power available to an individual has steadily increased over the last 60 years. Within another 20 years, the creation of a species-extinction virus will be accessible to most people with a reasonable background in molecular biology and access to the appropriate library and laboratory.
        • Just make sure we take no religeous people on the moon/mars colonizations. Because it would all just start again 200 years later with another nut case.

          When will people learn, instituionalized religeons are dangerous. Personal spirituality never does a crusade.
          • Maybe and maybe not. If the Earth population was wiped out by a religious fanatic, I suspect any space-based survivors would do whatever was necessary to avoid a recurrance, sort of the way hate speech and wars aren't very tolerated in Europe after 2 "World Wars".

    • Re:Think about it (Score:4, Interesting)

      by Rei ( 128717 ) on Friday January 13, 2006 @02:22PM (#14465909) Homepage
      Go ahead, tell me how you plan to make a self-sustaining colony on a body largely devoid of hydrogen, nitrogen, carbon and phosphorus, given that life on earth is based on CHONP? How do you plan to establish a chemical industry on the moon when it's mostly devoid of everything except O, Si, Fe, Ca, Al, Mg, Ti, and small amounts of Na, Cr, and K?

      The moon has a very non-diverse surface. It's not really possible to build a self sustaining colony on the moon - it will always have to trade heavily (and given current launch prices....)
      • I know this one... we'll make our elements in our nuclear reactors! That's just an interim plan, though, while we work to develop bacteria that can transmute moon rocks to useful elements in -- get this -- their NUCLEUS! A nuclear nucleus, isn't it great? It's amazing how evolution and breeding can solve any conceivable problem, like the lack of water or an atmosphere.
        • Actually, there is something to be said for using nuclear power to "crack" oxygen and hydrogen out of other materials. In any other environment it would be too expensive, but on the moon it might actually make sense.

          As for the rest of the stuff, the moon can purchase from providers who already have the necessary materials outside the Earth's gravity well. Who might that be, you ask? The companies who own mines on all the asteroids and comets, that's who. I mean, why oh why would anyone try to mine the moon?
          • Sure, it's theoretically possible to find various sets of nuclear fission that'll let you get hydrogen and maybe oxygen out of other nuclei, though it's not clear it'd ever be cost-effective (especially if there isn't a lot of convenient uranium lying around on the moon.)

            But the much more reasonable industrial process that cracks stuff into H, O, and leftovers is chemical cracking that uses the nuclear reactor as a heat source, so you can do things that are endothermic. On the moon, that might let

  • ... the proposal to make the miners permanent settlers...

    Why not just send up the thousands of criminals filling our penal system? Have them work the mines. We'll give them a ticket home when they've served off their sentance.
    • Oh yes and watch the amount of small time drug users who get rediculus sentences go way up.
    • Why not just send up the thousands of criminals filling our penal system?

      Because that's forced prison slave labor, and is the kind of human rights violation we rail against the Chinese for doing. Never mind other historical examples (including the US's). Though with an ethos accepting torture and imprisonment without fair trial becoming the norm, who knows? Maybe your dream will come true....
      • Okay, then do it like the current system. Prison labor still exists. The only thing is that it's not forced, and the prisoners have to be paid. However, they don't have to be paid minimium wage. The average federal prison wage (after penalties) is around $0.20/hr.
        • One might argue there is a fundamental difference between having prisoners (willingly) stamp out license plates vs. shipping them off to the moon in a low G environment. The long term consequences of living on the moon would almost certainly be damaging to their health. IMO: building a moon base for people is folly. Send robots.
          • Better idea: Ask for volunteers.

            The deal is: Stay on Earth and nothing changes. Go to the moon and you won't actually be imprisioned (since you can't go anywhere anyway), get a chance to earn some change, and have your sentence reduced or commuted. As a bonus, you get to be an astronaut. You can't tell me that there aren't at least a few dreamers in the lot who wouldn't jump at the chance.
            • Austronauts -- even prisoners -- must be safely shot in space, travel and land on the moon, be maintained in a survivable environment, and then shot back into space to return to earth. Robots can be sent to the moon in parts, will function in a wider range of environments, and can be disposed of on the moon. Which of the two is both the most ethical and cheapest?
              • Humans. Robots are a lot of money for little return. For example, a human on Mars could do in minutes what takes the Rovers months to accomplish. Humans are extremely adaptable to changing situations, and can actually cover ground extremely well on foot. In addition, they're excellent at building and operating a wide variety of tools.

                Robots are like computers. They're very good at optimizing something that's been done a million times before, and can be done the same way a million times again. They suck when they have to adapt to changing situations. Even when a human is nudging their controls from a distance, their use is extremely limited. As long as we're shooting robots into space to do our exploration for us, we're wasting time and energy that could be saved if we could go there ourselves.

                Which of the two is both the most ethical

                There's no ethical quandry. A lot of people want to go, and damn the risks. Risk is part of being human. (Why do you think we have all these skydivers and bungie jumpers?) If you don't want to take the risk, then don't. But don't tell other people what to do with their lives. THAT is unethical.
                • I disagree on both counts. While it's true that the current mars rovers are vastly limited in functionality compared to a human, a few technical generations of rovers will likely meet the threshold necessary to mine. And while a human being (even inside a bulky suit) may continue to have a dexterity advantage over remote technology for decades to come, success is measured not by total flexibility but simply by meeting the challenges of mining.

                  As for the ethical challenges: I think you're understating this i
                  • Well, that may not be the case. The level of gravity required for long-term survival and reproduction is very much an open question and we don't have any especially good ways to research less-than-normal gravity.

                    But the ISS element that was going to research that is looking less and less likely to be launched. So we really don't know.
                • "Humans. Robots are a lot of money for little return. For example, a human on Mars could do in minutes what takes the Rovers months to accomplish. Humans are extremely adaptable to changing situations, and can actually cover ground extremely well on foot. In addition, they're excellent at building and operating a wide variety of tools."

                  The one problem with your thinking is that the cost of life-support systems (including ensuring the vehicles don't accelerate too fast) is the most expensive part of manned

                • Re:The moon, tis a harsh mistress (Score:4, Interesting)

                  by flyingsquid ( 813711 ) on Friday January 13, 2006 @04:58PM (#14467419)
                  Humans. Robots are a lot of money for little return. For example, a human on Mars could do in minutes what takes the Rovers months to accomplish. Humans are extremely adaptable to changing situations, and can actually cover ground extremely well on foot. In addition, they're excellent at building and operating a wide variety of tools.

                  Humans have a lot of requirements that robots don't. Pressurized atmospheres, oxygen, water, food, mild temperatures, 8 hours of sleep a day, and soforth. All of that requires a lot of supplies and equipment, which costs a lot.The other major human disadvantage is that, unlike robots, they die.

                  Nobody freaks out when we leave a lander on Mars, but if we'd sent Neil Armstrong on a one-way trip to the moon and left him on the surface until he ran out of oxygen, there would have been outrage. Robots are disposable, but astronauts need a costly return mission. Death also means we can't take the same risks with people that we do with robots. Robots can achieve a high probability of success, cheaply, by having a large number of robots with a high probability of failure. Nobody would tolerate that with a Mars mission: you couldn't send two teams of astronauts to Mars and say, "Yeah, each team has a 25% chance of dying. But we're sending two teams, so the probability of BOTH teams dying is only 6.25%, and that's a 93.75% chance of mission success!" Astronauts might accept those kinds of risks, but the public would never accept it. If NASA slams a probe into Mars then Jay Leno cracks a joke; if the shuttle blows up, then it's a national day of mourning and the program shuts down for a year. So that means lots and lots of expensive backup systems for each mission.

                  As for agility, there has been a lot of success in building agile, legged robots recently (check out the cockroach-inspired running and climbing robots coming out of Berkeley). We should soon be able to build robots for things humans were never designed to do- like scrabbling over boulders in low gravity- and have them outperform anything a guy in a space suit could do.

                  • No, humans just need to not be headed for certain death.

                    Remember, most of the colonists who left their home countries didn't expect to come back. It was assumed that some of them would die even. But it was assumed that some would go off, prosper, and maybe even come back with sacks of gold.

                    I suspect that if you sent people on a mostly-one-way-mission to the moon with a sufficently large set of starter equipment, you could support them with a progressively-dwindling set of supplies over time, and nobody wo
    • We could call it "New Australia!"
    • I'm surprised how many people didn't get this...

      It's because they'll throw rocks back at us!
    • Nah

      I don't think we're ready for real AI.
    • Why not just send up the thousands of criminals filling our penal system?

      Ummm, because they might throw rocks at us?

  • doesnt that means we had to go there in the first place? dur [demon.co.uk]

  • Mankind has always and will always explore. That's how people spread across the globe. People braved massive oceans and inhospitable conditions just to see what lies ahead. It's who we are. None of the early explorers new if it would be worthwhile or profitable, but they did it anyways.

    With that said, humans have scoured this planet pretty well (except the oceans) and space seems like the natural next step. Do we know if it will be worth it? Of course not, but there are never any guarantees.

    http://relig [religiousfreaks.com]

    • Mankind has always and will always explore. That's how people spread across the globe. People braved massive oceans and inhospitable conditions just to see what lies ahead. It's who we are. None of the early explorers new if it would be worthwhile or profitable, but they did it anyways.

      That's a nice romantic notion, but unfortunately it's bullshit. Exploration has always been about profit, from the stone ages when people went in search of new food and game supplies, to Columbus looking for new trade route

  • Well fuck-a-duck (Score:4, Insightful)

    by AKAImBatman ( 238306 ) <<moc.liamg> <ta> <namtabmiaka>> on Friday January 13, 2006 @02:14PM (#14465823) Homepage Journal
    Schmitt's potentially inspiring commercial justification in Return to the Moon: Exploration, Enterprise, and Energy

    I can't believe it! That's my "three E's of space travel!" philosphy! The primary difference is "Economy, Energy, and Exploration" (in that order). Which is pretty much the same thing as "Enterprise".

    The only thing I don't understand is: What's with this obsession with fusion? Screw fusion. It's perpetually 20 years away. When the eggheads get it working, then we'll worry about going to the moon. Let's think a little more realistically. For example, massive mylar mirrors could focus gigawatts of energy on a space-based, close-cycle Brayton generator. The power can then be beamed back to Earth OR to all the other ventures happening in the solar system. And cheap power in space can mean cheaper costs for manufacturing and propulsion. Cheaper manufacturing and propulsion in space means $$$ for returning valuable materials from Asteriods. Of course, just like with the power, you need an infrastructure to support all that and bring prices down further. So a booming economy appears overnight to support this stuff. Venture capitalist smell money. Before you know it, we won't even remember what it was like when we didn't have space travel. :)
    • The power can then be beamed back to Earth

      And how, precisely, are you going to do that? And please don't give me that laser shit again, we don't have lasers powerful enough to beam back significant quantities of energy. Not to mention which there's no compelling reason to put solar collectors on the moon when we're not willing to invest in a deployment of them in the Arizona desert (for instance).

      • And please don't give me that laser shit again, we don't have lasers powerful enough to beam back significant quantities of energy.

        Why bother with lasers? High powered Masers are far easier to produce. Besides, you can use clusters of high-powered microwave transmitters. This leaves the option open of transmitted less power to more receivers. (A good thing.)

        Not to mention which there's no compelling reason to put solar collectors on the moon when we're not willing to invest in a deployment of them in the Ar
        • Again, do the math on how much energy is required and what sort of remote devices exist for conveying that power back to earch. It's not particularly close, the infrastructure isn't there or even near.
  • The reviewer says "the extra proton in helium means the ideal fusion temperature for He3-D mixtures is over four times as large ... .That makes the traditional approaches to fusion reactors, creating very hot and dense plasmas, essentially impractical for He3 fusion."

    Has the current consensus really ruled out tokamaks for D-He3 fusion? My understanding is that though it is obviously more difficult, that the benefits of this reaction might make it worth it. Anyone have any decent recent references?

  • Space travel isn't feasible (Score:5, Insightful)

    by Animats ( 122034 ) on Friday January 13, 2006 @02:24PM (#14465929) Homepage
    Space travel with chemical fuels isn't feasible.

    After half a century of building big rockets, we now know that they don't work very well. Half a century ago, they were use-once-and-throw-away devices, and they still are. Payloads are still tiny compared to the launch weight, even for the Shuttle. Compare the figures for jet aircraft, which can be half payload.

    Reliability is still lousy, too. This is because so much weight reduction is required just to get the things off the ground that they don't have adequate safety margins. About 10-20% of satellite launches still fail, almost half a century after the first one. That number isn't improving, either; in fact, it was a little better in the 1970s. There have only been a few hundred Shuttle flights, and it's crashed once. (Update since I wrote this in 2002: twice). Commercial aircraft flights, by comparison, fail a few times per year, out of millions of flights.

    Half a century in aviation took us from the Wright Brothers Flyer to the B-52. Half a century in rocketry took us from the Atlas I to the Atlas V. There's been little progress in launch vehicles since the 1960s. All the major launch systems were created decades ago. So chemical fuels just don't have the power-to-weight ratio for useful space travel. People knew this in the Orion nuclear rocket days; it's a straightforward calculation. It's unfortunate that an Orion wasn't launched once or twice, just to demonstrate that nuclear propulsion is possible.

    • Space travel with chemical fuels isn't feasible.

      Pfff. Is that your only complaint. We've got propulsion methods pouring out of our wahzoo. Lemme see, we've got Orion, Nuclear Thermal Rockets, Ion Engines, Magnetoplasmadynamic thrusters (MPDT), Mini-Magnetosphere Plasma Propulsion (M2P2), etc, etc, etc. And that's just the stuff we're sure will work. On the drawing boards we've Nuclear Salt Water Rockets, Daedalus Boosters, Antimatter propulsion, blah, blah, blah. The problem with all these methods isn't that they're inefficient, or that they won't get us where we're going. The problem is that ALL of them require you to obtain orbit first.

      What we're missing is cheap launch solution. There are currently no engines in existence that can provide a launch for less than ~$50,000,000. (Keep an eye on the Falcon rockets, though.) If you're using a super-booster to launch metric craploads of material, throwing away the rocket isn't so bad. But just to transport a few people or light cargo to orbit, we STILL have to throw away the rocket OR use a rocket that's so overdesigned it costs more to maintain than a throw-away rocket. (aka The Space Shuttle. Marvel of engineering, marveled by shocked accounts.)

      We need to go back to 1975 and pick up the pieces where we left off. Instead of a Space Shuttle capable of carrying cargo, we need a fully reusable SSTO (Single Stage To Orbit) Space Shuttle that keeps costs down. Instead of a Space Shuttle that launches a mere 27ish tonnes of cargo, we need a super-booster that can carry upwards of 100 metric tonnes of cargo. Instead of a Space Station that's sitting in the wrong orbit to do anything useful, we need a Spaceship Garage in space capable of building, repairing, manufacturing, and staging inbound/outbound flights to the rest of the solar system.

      The CEV project is on the right track, but we'll have to see if the higher ups eventually pull their heads out and start supporting missions and technology that will go somewhere rather than making some politco happy with his pork.
      • Lemme see, we've got Orion...The problem is that ALL of them require you to obtain orbit first

        I bet you could launch something into orbit with an Orion drive. Just don't plan on coming back for a few thousand years.
        • I bet you could launch something into orbit with an Orion drive.

          Actually, you can launch a LOT of something into orbit with an Orion drive. The original Saturn mission was slated to ground-launch from Jackass flats Nevada, and would have carried about 3,000 metric tonnes of spaceship, personnel, and cargo into space. The plan had to be cancelled after the Nuclear Test Ban Treaty went into effect.

          Orion didn't die, however. It was still a viable concept (and still *is* a viable concept) for a space drive. The

      • Re:Space travel isn't feasible (Score:4, Interesting)

        by kesuki ( 321456 ) on Friday January 13, 2006 @03:52PM (#14466753) Journal
        you forgot space cannons. http://www.daviddarling.info/encyclopedia/S/spacec annon.html [daviddarling.info] hello 1950's technology we need your help again ;) all weather launches of cargo to orbit or go to the moon (as long as they can survive 10,000 Gs of acceleration, and are narrow) for a fraction of the cost of conventional payloads.
      • Or use laser or microwave tech for the launchers. Why carry the energy with you?
        • Lasers don't have enough thrust to push something into orbit. They work great once you're already in space, but not so good on the ground. All the launch proposals involving lasers actually propose using the laser as a method of exciting the propellant. SO, unfortunately, you still have to carry the propellant with you. You can drop the engines, though.
  • No matter what the subject, one has to admire a book written by an astronaut and former US senator

    Really, so if an astronaut becmoe senator writes a cheesy fictionaly thriller novel, or My Ten Favorite Women's Undergarments we'd still have to admire it because of the author?

  • Back to the Moon (Score:2, Interesting)

    by Petaris ( 771874 )
    This seems to have a lot of similarities to the book "Back to the Moon" by Homeer H. Hickam.

    http://www.homerhickam.com/books/moon.shtml [homerhickam.com]

    Other then Back to the Moon is meant to be science fiction, the author did explain that the Helium 3 fusion theory that was one of the main plot points in the book was not science fiction. Over all it was a good read and unlike many sci-fi novells most everything in it was feisable with current technology. After all, it was written by a NASA engineer.

    If you are looking for
    • Back to the Moon was a cute book, but Hickam glossed over a LOT of details there. According to some back of the envelope calculations [homeip.net] I did, the astronauts were severely short on fuel. So in short, they never should have made it to the moon in the first place. His "Big Dog" engines would have to be the most powerful engines ever designed (including all but the most exotic stuff on the blackboards) in order to propel the Space Shuttle to the moon on the fuel from a single commercial launch.

      Or to put it anoth

  • Spacedaily picture links (Score:3, Informative)

    by bhny ( 97647 ) <bh@u[ ]net ['sa.' in gap]> on Friday January 13, 2006 @03:06PM (#14466326) Homepage
    for some reason the pic links on spacedaily are wrong. the links are to erosdaily.com - (someone's joke?).

    this link works-
    http://spacedaily.com/images/apollo-schmitt-rock-1 280.jpg [spacedaily.com]
  • Maybe we should first raise taxes to build all the antigravity gyroscopes, antigravity superconductors, and static electricity lifters which have ever been invented before we solve all our problems when the helium-3 fusion on the moon.

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