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One Small Breath For Man 280

An anonymous reader writes "The New York Times reports on a new technique that may allow Oxygen to be wrung from the soil on the moon. This may pave the way for a moonbase, and allow permanent habitation on Earth's only natural satellite." From the article: "Lunar soil brought back to Earth is in short supply and highly prized, so Nasa researchers have been using matter with the same composition for its tests. The soil contains about 45 per cent oxygen by weight, but it is mostly 'trapped' in the form of silicon dioxide ... At the moment, all oxygen supplies would have to be brought from Earth, which is so expensive and energy-inefficient that it effectively rules out a permanent Moon base. "
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One Small Breath For Man

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  • by Anonymous Coward on Monday May 29, 2006 @02:00AM (#15423412)
    Oxygen don't grow on trees.
  • Water (Score:5, Insightful)

    by MichaelSmith ( 789609 ) on Monday May 29, 2006 @02:00AM (#15423416) Homepage Journal

    I predict that if hydrogen can be extracted from regolith close to the surface, then a lot of that oxygen will be burnt down to make water. During the apollo [nasa.gov] missions oxygen had to be carried but more often than not water for cooling was the limiting factor for stays on the surface.

    Its nice to see that people are working directly on this, even if it will be at least 15 years before anybody walks on the moon again.

    • On the other hand, they could just breathe it. Human respiration produces H2O as a waste product; it could be condensed in the ventilation system.
      • Homan breathing produces CO2. It contains H2O, but it doesn't produce it.
        • While this may get modded redundant, you need to check your facts; check above: Inspired air contains very little H2O, whereas expired air contains much more since what you're respiring (Glucose and fatty acids, for the most part) contain what we in the business know as hydrogen. When you burn a hydrocarbon, such as all foods are, you get CO2 and H2O.
    • I predict that if hydrogen can be extracted from regolith close to the surface, then a lot of that oxygen will be burnt down to make water.

      I predict that if anything can be extracted from the regolith close to the surface, it will run out so fast that after a few weeks, expensive subsurface mining and/or far flung harvesting will be made necessary, thus defeating the point of the entire excercise.

      I don't know about you, but I think ore harvesters on the moon is simply not a feasable option. They cost $1400 a pop after the first!
  • Isn't energy enough? (Score:5, Interesting)

    by Bombula ( 670389 ) on Monday May 29, 2006 @02:01AM (#15423419)
    I am no chemist, but I thought that with enough energy it is usually possible to break up compounds into their constituent elements. Is energy in short supply on the moon? Seems like solar and possibly nuclear energy from the moon's deuterium should be able to supply lots of energy. Am I completely retarded here? Probably...
    • by Cadallin ( 863437 ) on Monday May 29, 2006 @02:26AM (#15423489)
      No, you're exactly right. Much of the lunar dust is Si02, the same as sand or glass or quartz.

      SiO2 + energy -> Si + O2

      Is perfectly valid chemistry. In fact, if you go back to the hard sci-fi of the 50's and 60's this is the kind of shit they predicted we'd be doing RIGHT NOW. Building plants on the moon to convert lunar dust to oxygen (and high quality silicon for chip fabs) for both lunar bases and space stations.

      • by tm2b ( 42473 )
        In fact, if you go back to the hard sci-fi of the 50's and 60's this is the kind of shit they predicted we'd be doing RIGHT NOW.
        Sadly, it's actually the kind of shit they predicted that we'd be doing 10-20 years ago.

        After all, we first made it to the moon 37 years ago... I don't think anybody dreamed that far ahead that we'd abandon it once we achieved it.
    • I am no chemist, but I thought that with enough energy it is usually possible to break up compounds into their constituent elements.

      Which is exactly what they propose doing. To do it on an industrial scale; under lunar conditions (vacuum, solar heating) details need to be worked out. The basic chemistry is trivial. Si02 + energy = Si + O2

    • by mattmacf ( 901678 ) <mattmacfNO@SPAMoptonline.net> on Monday May 29, 2006 @03:09AM (#15423581) Homepage
      I'm no chemist either but I did take a high school chem class a few years ago. I'm far from confident in my calculations, so feel free to correct me if I'm egregiously wrong, but AFAICT the amount of energy needed might be a limiting factor. Now, the article gives us two tidbits of information.
      In Nasa's latest tests, a 12ft-wide dish was used to concentrate the sun's rays on to 100g of a substance similar to Moon soil. After a few hours, one fifth of the substance had turned into oxygen.
      and
      The soil contains about 45 per cent oxygen by weight, but it is mostly 'trapped' in the form of silcon dioxide.
      Now assuming that one fifth of the 45% of the oxygen in the soil is 100% oxygen, we yield a total of 9g of pure oxygen. A quick trip to Google [google.com] tells us that oxygen has a molecular weight of (roughly) 16. Therefore, 9g of oxygen translates to 0.5625 moles of pure oxygen. Another check of Google [google.com] tells us that the volume of oxygen at STP is 17.36 x 10^-6 cubic meters/mole. We finish our Google-sponsored portion of this post by converting [google.com] to give us 17.36 mL/mol. Multiplying by our previous result (0.5625*17.36) gives us a whopping 9.765 milliliters of oxygen. So how much exactly is that?

      We continue our inquiry at the wonderful world of Wikipedia. We learn that the Earth's atmosphere [wikipedia.org] is only 21% oxygen, so our 9.765 mL of pure oxygen effectively becomes 46.5 mL of normal air. Our final reference [wikipedia.org] tells us that the average human breath exchanges 450-500 mL of air.

      Putting this all together, we get a notably unimpressive result. The "few hours" that it takes to bake oxygen out of moon sand creates only enough oxygen to support one-tenth of one ordinary resting breath for one average-sized adult male.

      I really hope I'm off by an order of magnitude or four, but unless I'm terribly wrong (entirely possible), this technology has a long way to go. The final line of the article does give hope, however: "Alternative methods to extract oxygen from Moon soil are also under investigation, including melting the rocks into a liquid and freeing oxygen with an electric current." Obviously NASA realizes this plan still needs work. Hopefully

      • Not Quite (Score:5, Informative)

        by FasterthanaWatch ( 778779 ) on Monday May 29, 2006 @03:25AM (#15423618)
        The standard molar volume of most any gas is still 22.4 L/mol so 8g of Oxygen would be 5.6L of oxygen. Throwing in a ratio of 25% Oxygen, and we end up with over 20L of air.

        Still not sure how you got that other figure, but perhaps it refers to the liquid form.

        • That's the standard volume 1 mol of ideal gas takes up at 0C, 101.3kPa. Ideal meaning gas which isn't attracted to/repelled from itself, and doesn't have any mass. But oxygen's close (enough for our purposes), so your correction is still valid.
        • Re:Not Quite (Score:3, Insightful)

          by oringo ( 848629 )
          Grandparent's calculation also failed to point out that human respiration does not consume 100% of the oxygen in the air. Dry air contains about 20% oxygen, and exhaled (consumed) air contains about 16% oxygen. To make the air breathable again, you only need to replace the 4% consumption. Assuming that you can remove the CO2 in a reasonable speed, the 20L of breathable air (flow) can easily be turned to 100L of breathable air (flow).
          • Removing the CO2 is relatively easy process. Get a SCUBA diver to tell you about the way oxygen scrubbers work. I think it involves a zeolite (quartz crystal is a zeolite) of one or another composition - which, by the way, can be synthesized out of silicon and hydrocarbons.
        • Wow. Heat the air up to insane temps then cool it down to LOx temps.

          Someone thinks they've got heat transfer physics down better than they do: Sure sure, it's eay to concentrate sunlight, but where does one expel the heat to cool the resulting oxygen?

          *blinks*

          Oh, nevermind. You can use the hot side of the radiator to preheat the feedstock (which would be coming from the now-cooler ring of lens shadow).

          Or, the process could be done is cycles based on the lunar day; during the night, the lunar surface is dam
      • Skipping all the conversions.
        NASA states an adult requires 840g of oxygen. One dish and a 100g of soil in a few hours got 20g of oxygen. The sunlight was going through atmosphere so I'd think it would be more efficient on the moon, but we'll stick with the 20g. 4.2kg of soil and 42 dishes would supply enough oxygen for one adult in a few hours, Maybe? 4-6 adults a day.
        The Biosphere 2 lost oxygen at a rate of .3-.5% a month(can't find it in grams). So could a Biosphere 3 with added oxygen from this process b
      • I think you misinterpreted the quotes you used as the basis for your calculations. The important part of the first quote is After a few hours, one fifth of the substance had turned into oxygen. To me, this says that one fifth of the total mass of the soil ended up as oxygen; you seem to have taken it to mean one fifth of the available oxygen in the substance. The quote says no such thing, and does not reference the 45% number out of the second quote; those two facts (the composition percentage and the yield

      • A quick trip to Google tells us that oxygen has a molecular weight of (roughly) 16.

        That's the average atomic weight of Oxygen. We breathe O2, which has a molecular weight of 32. As another reply mentioned, a mole of any gas at STP is 22.4L. So 9g of oxygen is 9/32 * 22.4 L, or 6.2 L.

        20% O2 is nice and breathable, so you could make 5x as much air by using "recyclable" nitrogen as filler. That would be over 30L of air from 9g of oxygen.

      • We learn that the Earth's atmosphere is only 21% oxygen, so our 9.765 mL of pure oxygen effectively becomes 46.5 mL of normal air

        The article mentions that they would be breathing 100% oxygen. At STP thats not a good idea, but the pressure can be reduced so that the partial pressure of oxygen is the same as at STP (something like 3psi). This allows one to breath pure oxygen without harm, reduces the structural demands of containing normal atmospheric pressure, and the low pressure does not result in the fi
    • I think this should be modded up.

      One of my mentors at school (an amazingly talented man) pointed out to me that with enough energy, there is virtually nothing you can't do if you can can apply the energy the way you want. Efficiency doesn't matter if you have enough.

      On the moon, it's a matter of taking the differences in environment (from Earth) and turning them to your advantage. So, for example:

      Solar energy: No problem - no atmosphere, no clouds etc.

      Nuclear energy: Fission. A lot of the weight of an E
      • by shawb ( 16347 ) on Monday May 29, 2006 @05:12AM (#15423852)
        Nuclear energy: Fission. A lot of the weight of an Earth bound nuclear reactor is shielding and safety equipment which is (quite rightly) mandatory. On the moon? "Oh hell, the reactor's melted down. Good thing we sited it 100Km from the base". BTW. We *have* sent nuclear reactors into space - you don't think Voyager is running on car batteries, do you?

        The Voyager probes are technically nuclear powered, but it is not the same beast as in a chain reaction fusion reactor. The probes use an RTG [wikipedia.org] which converts some of the heat released from natural radioactive decay into electricity. These do not produce electricty on nearly the same scale as a thermal fission reactor. The RTGs in the Voyager probes are generating about 300 Watts. That couldn't even power some gamers' desktop computers, much less a large scale SiO2 -> Si + O2 manufacturing process. Granted, a large number of RTGs could be used, as well as using larger and more efficient RTGs, but it seems likely to me that the amount of PU-238 (as well as some of the more exotic materials needed to drive the process would be cost prohibitive for any useful amount of oxygen.

        All that, and RTGs still need a way to get rid of excess heat, as a thermocouple relies on the difference in temperature to produce electricity. The amount of heat that needs to be removed from a voyager level RTG is not that significant and can probably be accomplished through simple radiation, but the amount needed to drive a major industrial process would require some fairly exotic cooling techniques (although on the lunar night a good portion of the waste heat could be reclaimed to heat living quarters, etc.
  • by Anonymous Coward on Monday May 29, 2006 @02:03AM (#15423424)
    Picture it. Fights between "our reserves are finishing soon" versus "it's going to last for long".
    Campaigns on the line of "Have children, they'll only take n cubic metres of soil per year".
    New religions venerating resurrection via burial: "Oxygen you are and in oxygen you'll become".
    Mr President Of The Moon declaring "We as a nation have an addiction to oxygen".
    • by Anonymous Coward
      Islamic nations happen to land on the highest deposits of oxygen. And then the Americans go in to "liberate" them. And just coincidentally steal their oxygen deposits...
  • by dotmax ( 642602 ) on Monday May 29, 2006 @02:04AM (#15423425)
    At the risk of sounding jaded or complacent, this sounds awfully familiar, decades-old familiar... it sounds like the news isn't so much the process as the plan to send real world hardware up for a test run?

    the real challenge to my mind sounds like a)keeping the machinery functioning for more than a few days and b) keeping the furnace's optics from collecting too much dust. I wonder how they plan to address the dust-related issues.

    all in all, it sounds way cool. Best of luck to everyone involved.

  • Dammit! (Score:5, Funny)

    by Arivia ( 783328 ) <arivia@gmail.com> on Monday May 29, 2006 @02:07AM (#15423436) Journal
    The article title made me think /. had finally opened its' much-awaited Corsetry section...
  • by green1 ( 322787 ) on Monday May 29, 2006 @02:09AM (#15423440)
    while it's true that at the moment oxygen has to come from earth to the moon, the same is true for food. it would seem to me that the only viable solution to getting food and oxygen to a base on the moon, isn't to bring it from earth, nor is it to "mine" it from the moon, but rather to build a self sufficient environment, if you are talking about a permanent base on the moon, wouldn't it be prudent to build a base with it's own small eco-system? the right plants, it would seem, could provide both oxygen and food...
    • ...but to begin with, and to establish the base, a large parabolic reflector is a whole lot quicker and less finicky to set up than a hydroponic air-farm.
  • by techno-vampire ( 666512 ) on Monday May 29, 2006 @02:09AM (#15423443) Homepage
    Oxygen isn't as hard to bring from Earth as you might think. Not only do you have to bring air to breath, you have to bring water, both for drinking and for cooling. Once a base is set up, some of that water can be broken down, releasing oxygen. Not only that, the food you carry there also contains oxygen. Part of the base will be a greenhouse, fertilized by waste products and converting CO2 into O2, plus part of the colonist's food supply. If there's too much organic waste, some of it can be incinerated, leaving (mostly) water and CO2, both of which the greenhouse can use. Yes, if we can't get much oxygen out of the regolith, we'll have to ship it up, but that's a one-time expense, not an ongoing one.
    • uh yeah, because vacuum seals are 110% effective and never ever leak, and once you establish the base, you'd never want to EXPAND IT. And it not like it would be 100's of times cheaper to ship oxygen generated on the moon to a space station/other orbital facility than the earth, no siree.
      • Of course there'd be leaks, and of course you'd want to expand. However, once the base was established, most of its needs could be satisfied by recycling.
        • Yes, but that's not the point. Oxygen would be produced as an industrial by-product from any number of activities on the moon, once you got it all started: Mining, both aluminum and Titanium would be both useful and profitable, as well as trace iron deposits. Silicon would probably be a fairly big deal, as growing absolutely pure silicon crystal wafers would be easier on the moon. And there are significant space industry uses for all that excess oxygen, particularly given that it is much easier to get f
    • Oxygen isn't as hard to bring from Earth as you might think. Not only do you have to bring air to breath, you have to bring water, both for drinking and for cooling

      TFA doesn't go into it, but the major use of a lunar oxygen plant would be as fuel, rather than breathing. For return trips to earth, or hopefully to orbit, asteroids, Mars.... Of course, they'd also need hydrogen, but even if that can't be found easily on the Moon, it's a lot lighter than oxygen to haul up.

    • Once a base is set up, some of that water can be broken down, releasing oxygen.

      Oh, absolutely not. That is a very silly idea for two reasons.
      One, you will need every droplet of water you can get. Have you learnt nothing from the droughts that even England (of all places!) manages to suffer from?
      Two, if you are going to transport a X litres of water up there just to break it down into oxygen, you might as well be efficient and transport X liters of compressed oxygen instead. Why bother with all the hydroge

      • One, you will need every droplet of water you can get. Have you learnt nothing from the droughts that even England (of all places!) manages to suffer from?

        What does England have to do with it? Unlike a Lunar colony, the English climate is an open system; the colony's will be as closed as possible. As far as needing every drop of water you can get, don't you know that one of the byproducts of metabolism is water? Given time, you'll have more than you need. I wasn't thinking about breaking it down right

      • It also only really addresses the problems of the initial transportation costs if you're a creationist, because then there is prior evidence that such a system can be set up in seven days flat (you might even have time to rest at the end).

        True, with one additional requirement, infinite power (or enough so as to make no practical difference). Of course, with enough power and the ability to control it, anyone can make anything and we can skip little issues of where the stuff has to come from or how we ship i
  • How do we get NY Times out of a British site?

  • by Inda ( 580031 ) <slash.20.inda@spamgourmet.com> on Monday May 29, 2006 @02:19AM (#15423471) Journal
    Fact: Silicon dioxide is also known as silica.

    Fact: Inhaling crystalline silica dust can lead to silicosis or cancer.

    I thought they were amusing facts. +1 Important please Mods. :)

    • Fact: Inhaling crystalline silica dust can lead to silicosis or cancer.

      I can think of much more interesting things to inhale than sand, such as, say... asbestos.
    • Good point -- there could be a real hazard there. Maybe the filters in the air system would have to be HEPA?

      There's also been worry about lunar dust getting tracked in to the habitable area on spacesuits. Here on Earth we'd approach problems like that by showering everything with water, but a moon base won't have much spare water.
  • ...so the news today is that sand contains silica...or that moonsand itself contains it...well, I'd better read the papers this morning.

  • by Derosian ( 943622 ) on Monday May 29, 2006 @03:13AM (#15423590) Homepage Journal
    I was looking at a Ramen ingrediants list while reading this, and I found out that the Soup Base has Silicon Dioxide in it... Does this mean Ramen is carcinogenic? And better yet.... Does this mean we can make Oxygen from Ramen if the need arises?
  • pure oxygen (Score:3, Interesting)

    by penguin-collective ( 932038 ) on Monday May 29, 2006 @03:34AM (#15423634)
    Contrary to what the article says, pure oxygen is toxic to the lungs, at least at standard pressures. It may be possible to reduce pressure, but I think the long-term effects on humans of breathing pure oxygen at a significantly reduced pressure are still unknown; I wouldn't want to subject myself to it.
  • soil? (Score:2, Insightful)

    by SilentGhost ( 964190 )
    It's not a soil. It's ground. Calling it soil implies idea that there are some living organisms there. which is incorrect.
  • Fine, let's stripmine the moon for oxygen and small amounts of water using equipment transported from Earth at immense expense just to prove we can place a few gravity-maimed individuals on a Moon base or "colony" there.

    The moon is a desert. It it a desert like no desert on the face of the Earth. We know that. Let's not engage in senseless activities just because we can. Let's not rape the public purse to satisfy bored scientists or political ego.

  • I thought the elements that were virtually absent on the moon, while being essential for life, were hydrogen and carbon. That's the hard part. You have to bring it all from earth. The article is about oxygen which is in abundant supply. The oxygen part is interesting for the reason that it's simple enough to provide the first instance of actually mining the moon.
  • Can we please have headlines which actually tell something of the story rather than try to be clever? Some of us use the rss feed.
  • welcomes it's new oxygen-breathing overlords.
  • by jmh55 ( 307345 )
    Air on earth is ~78% nitrogen by volume (and ~75% by mass), whereas moon base air would be 100% oxygen. There seems to be a couple of problems with this:

    1.) At 100% atmospheric oxygen, clothing and hair (and lots of other things I'd guess) become highly flammable, even explosive.

    2.) People aren't designed to breathe pure oxygen for extended periods. While it's essential for life, it's also rather toxic - http://en.wikipedia.org/wiki/Oxygen#Precautions [wikipedia.org]

    So, unless there's another element up there to dilute the

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