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Mars Space Science

Martian Methane May Be Created By Lifeforms 297

Posted by kdawson
from the little-green-bugs dept.
Following our recent discussions about the growing evidence pointing to possible life on Mars, reader skywatcher2501 writes with news of a study that has ruled out one possible explanation for the levels of methane seen on that planet — that it might be replenished by disintegrating meteors entering the atmosphere. So two theories remain: either the gas is created as a by-product of reactions between volcanic rock and water, or it is a by-product of a lifeform's metabolism.
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Martian Methane May Be Created By Lifeforms

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  • by gregarican (694358) on Tuesday December 08, 2009 @03:51PM (#30370112) Homepage
    that Martians need some beano eh? Also, first post BTW...
    • "Excuse me" said Marvin the Martian.

    • I thought I had heard that Mars' atmosphere is weak because the plant's core is not molten like the core of Earth. Is this still the theory?

      For those who aren't familiar with the idea, Earth's molten core creates a magnetic field that blocks the solar wind from the Sun. The solar wind would blow away Earth's atmosphere if it weren't there.

      So, if Mars somehow got a molten core, by adding mass, or simply spontaneously, air would remain, then seas could form, etc.

      The presence of methane from biologica
      • Re:Life on Mars (Score:5, Insightful)

        by realityimpaired (1668397) on Tuesday December 08, 2009 @05:15PM (#30371210)

        Mars has about 1/2 the radius of the Earth and about 1/10th the mass, which means a significantly smaller gravitational field, even at the surface (about 1/3 the gravity at the surface, and remember that it falls off proportionately to the square of the distance from the center of mass).

        While Mars doesn't have a magnetic field any more, I suspect that the reason that Mars's atmosphere is so much thinner than our own has more to do with the lack of mass and corresponding gravity well to hold the gases in than it does the solar wind blowing it away. Recall that Mercury has a magnetic field, and it doesn't really help the planet hold its atmosphere. And lest you think that's because it's so close to the Sun, and thus the subject of stronger solar winds, I'll point out that Ganymede also has a permanent magnetic field and a very thin atmosphere, but its surface pressure is so low that if it were created in a bell jar here on Earth, it would be considered a vacuum.

        • Re:Life on Mars (Score:4, Informative)

          by holmstar (1388267) on Tuesday December 08, 2009 @05:32PM (#30371408)
          Titan, which is quite a bit smaller than Mars, has an atmosphere 1.5 times as dense as Earths.
          • Re:Life on Mars (Score:4, Informative)

            by infinitelink (963279) * on Tuesday December 08, 2009 @07:33PM (#30372646) Homepage Journal
            Titan is also extremely cold, and has less agitation of its atmosphere; it has protection from Saturn's magnetic field (which it may be holding onto as it does pass through) and is at a much greater distance from the Sun than Ganymede is; the gases compositing the atmospheres of each are also different, which in consideration of their properties may definitely matter: my point is, that neither singly mass, nor density, nor solar distance, nor composition, nor magnetic properties, i.e. any single variable, is responsible for atmospheric density. Mars, however, is both so close to the Sun to be affected by solar winds, and so mass deficient relative to those other factors, that the planet isn't adequate for holding onto a dense atmosphere (of almost any composition): if it were around a dead star, or floating through space away from agitations, etc., then sure, you'd expect it could hold a dense--perhaps frozen (as much of Mars's atmosphere may, in fact, be, and thus on its surface and in its soil)--[r] atmosphere; but considering the variables for holding the kind of gases we'd even be interested in, it's not much worth our time, except perhaps to mine, or for other conditions for experimentation.

            The same, unfortunately, applies to Venus--is inadequate to hold onto the kind of atmosphere we'd be interested in, and would even if its role were reversed with Mars (which would also mean it would be too cold). We on Earth have the sweet spot positionally, in mass, gravitationally, in density, and all the other variables you could think of. I'm happy for it too! : )
      • Re: (Score:3, Insightful)

        by meerling (1487879)
        Some of the recent studies show that it's incomplete magnetic field is actually accelerating the loss of atmosphere.
        Apparently those magnetic domes that were once thought to help retain atmosphere are now acting like ski ramps to help the solar winds blow off more air than if Mars had no magnetic field whatsoever. That's really gotta suck.

        Of course, that doesn't preclude the existence of some form of extremophile.
        After all, it's had millions of years to adapt to the changing environment that is Mars.
        On the
  • by Anonymous Coward on Tuesday December 08, 2009 @03:51PM (#30370116)

    Methane concentrations peak in an area on the planet opposite the famous face on mars.

    • by Stargoat (658863)

      I was wondering if they have fingers to pull.

  • crap (Score:3, Funny)

    by Nadaka (224565) on Tuesday December 08, 2009 @03:54PM (#30370138)

    Now the ecozealots will decry our spoiling of the natural martial environment, and will protest any attempt at colonization or terraformation as the destruction of a precious natural world.

    • Re:crap (Score:5, Insightful)

      by oldspewey (1303305) on Tuesday December 08, 2009 @04:06PM (#30370292)

      Well from a purely scientific standpoint I'd say there's merit in preserving and studying life forms that have evolved in complete isolation from anything on Earth.

      Wouldn't you?

      • Or did they? (Score:5, Insightful)

        by scorp1us (235526) on Tuesday December 08, 2009 @04:12PM (#30370402) Journal

        I saw recently that NASA was leaning towards judging structures on a few meteorites as organic in nature. Meaning, we could have been derived from, or seeded life on Mars. Multiple times.

        • Parent poster wasn't really talking about abiogenesis but evolution (perhaps he used too strong words, "complete isolation")

          Even if there was some exchange of material at the beginning, any lifeforms that subsequently conquered any of the two planets would be evolving in isolation.

      • by djtachyon (975314)
        Who says we aren't already [xenotechresearch.com]?

        muahahahah! .. seriously look through some of this guys endless hours of image and "fossil" comparing .. wacky.
      • Re: (Score:3, Funny)

        by WoodenTable (1434059)

        Indeed. The scientific value of alien life is immense, rivalled only by its potential for deliciousness.

    • Re: (Score:3, Insightful)

      by MightyMartian (840721)

      I would think before we start transporting over all our microbes, we might actually want to make a reasonable attempt at determining whether Mars has some of its own. Certainly in the interests of biology and xenobiology this would be a critical bit of knowledge. We ain't always gonna be stuck just in this solar system, and if there are a few spots in our neighborhood that harbor life, to assure that we gain as much knowledge as possible about alien biology and ecology, it's in our best interests to not p

      • Ceres the newly reclassified "Dwarf Planet" is a far better place to set down roots, you don't need much to "take-off" from the surface maybe something slightly stronger than maneuvering jets. Plenty of water to sustain life and plenty of mass to build structures on. It is farther out than mars but it is a good mix between the convenience of an asteroid and the convenience of a planet. Plus you are further out from sun so less protection from solar flares is needed.

        The only thing limiting it's coloni

        • I agree completely. The Moon, like Mars, is a big gravity well, and it's expensive and energy intensive to get on and off these things. The asteroids and planetoids are far more sensible, plus they likely have much easier to access volumes of valuable ores. Go to the Moon or Mars, and you're faced with all the standard geological and engineering problems of mining, with the added detriments that you are now also operating in an extremely hostile environment. For the Moon, solar radiation is going to mea

  • "There's something alive in here!"
  • I do hope... (Score:4, Insightful)

    by Dartz-IRL (1640117) on Tuesday December 08, 2009 @03:55PM (#30370148)

    That it is life. I've said it before so I won't reiterate with a long post, but if there's life on Mars, that proves life isn't just unique to Earth. This planet isn't a fluke. If there's life on Mars, then it can be *anywhere*

    What an amazing thing that would be.

    Almost as good as the BBC TV series...

    • by abbynormal brain (1637419) on Tuesday December 08, 2009 @04:03PM (#30370240)

      ... get ready to hear this word a lot: "cross contamination" from the bombardment period.

      I know - I know. I'm not advocating it - I'm just saying: Don't be surprised.

      • by pluther (647209)

        It's quite possible.
        If there is life on Mars as well as Earth, that would be a reasonable explanation of how.

        However, it doesn't change the fact that if it's there, it could be *everywhere*. Cross-bombardment works everywhere else just as well as between Mars and Earth.

        If we do find it, the next step of course is to go there and analyze it. Is it related to us? How far back? Does it even use DNA? What kind of ecosystem can exist in the conditions it's living in?

        Of course, the first step is still to dete

        • The next step is to make sure that, in "go[ing] there and analyz[ing] it", we don't destroy it.

    • by lattyware (934246)
      I loved that series. Then I watched the American version, the ending to that was truly, truly horrible.
      • by sznupi (719324)

        ...though, from what I know about it, it kinda fits with recent "safety first" policy at NASA? :/

    • Re: (Score:3, Interesting)

      by blincoln (592401)

      Almost as good as the BBC TV series...

      A little off on a tangent, but I was just watching another BBC series (Planet Earth - I know, I'm a little late to that party), and there are numerous extremophiles covered in it. I knew about some of them already, but I was particularly surprised at the bacteria and animals that live in naturally-occurring sulfuric acid.
      I'd been doing a little reading about bacteria that live off of the sulfur cycle (as opposed to the carbon cycle) already because my multispectral phot [beneaththewaves.net]

    • Well perhaps... Perhaps Life is still unique in the universe. However some bacteria which came from mars went in spore form to earth and found it was a good place to grow, or the other way around. We could find life within our solar system. But that is it.

      • by sznupi (719324)

        No, we can do much more.

        With proper telescopes, coming relatively soon, we will be able to determine the atmospheric composition of Earth-like planets.

        Finding one with atmosphere similar to Earth is a very strong argument for existence of similar lifeforms.

  • ...that would have to be a lot of life, no? Or would the gas have been created by long-dead/extinct lifeforms, and the gas is just that stable in the atmosphere?

    Also, titan is almost literally drowned in Methane (as in, lakes and oceans of the stuff). There ain't that many meteors floating around for that volume, and there's no volcanic activity to speak of, IIRC.

    • Re:Questions: (Score:5, Informative)

      by Yetihehe (971185) on Tuesday December 08, 2009 @04:00PM (#30370202)
      The problem is that on mars all methane should vanish in months due to oxidizing soil. Therefore something must be replenishing it.
      • Re:Questions: (Score:5, Interesting)

        by vlm (69642) on Tuesday December 08, 2009 @04:31PM (#30370602)

        The problem is that on mars all methane should vanish in months due to oxidizing soil. Therefore something must be replenishing it.

        Its a more complicated problem than that. First of all, there is no viable explanation for a source, assuming no lifeforms on mars, no active volcanoes, not enough meteors... Secondly, methane is localized and produced at weird rates, almost like weather... errr growing seasons... Third, methane is photochemically unstable in UV, it should all disappear in a couple centuries, except it is measured as disappearing much more quickly, VERY coincidentally about the timeframe of one martian year, so grasping at straws, it must be "oxidizing soil" or something. Fourthly the ESA guys claim when they detect methane, it also coincidentally comes along with yummy water vapor (actually, probably fizzy carbonated water crossed with stinky swamp gas)

        http://en.wikipedia.org/wiki/Atmosphere_of_Mars#Methane [wikipedia.org]

        Now it is refreshing after the quack climatologists basically making stuff up to "prove" their hypothesis, to see that real scientists studying mars are very carefully and appropriately skeptical about declaring martian life. But eventually Occams Razor kicks in and the complicated non-life workarounds become more ridiculous than admitting it makes more sense to assume there's life on mars. I think that tipping point is extremely close.

  • by Glock27 (446276) on Tuesday December 08, 2009 @03:58PM (#30370178)
    Another possible explanation might be ancient underground methane deposits leaking into the Martian atmosphere...if this has been ruled out, how?

    It seems possible that life existed in the distant past on Mars, leaving behind methane deposits much like oil and natural gas deposits here on Earth...

  • by quangdog (1002624) <quangdog@gm[ ].com ['ail' in gap]> on Tuesday December 08, 2009 @03:59PM (#30370198)
    This spells disaster in the form of global climate change on mars! Who wants to be the first to martian up and buy some methane offsets?
    • Re: (Score:3, Interesting)

      by jameskojiro (705701)

      Carbon offsets are for Methane too as Methane is C(H4)...

      • Re: (Score:2, Interesting)

        by oldspewey (1303305)
        The latest issue of WorldWatch magazine had an interesting piece on the contribution of methane to AGW ... the general conclusion was that convincing humans to alter their diet (less/no meat) will have more impact than convincing them to alter their driving habits.
        • Re: (Score:3, Interesting)

          by jameskojiro (705701)

          Obviously the solution is to genetically engineer the bacteria in ruminant stomachs to produce no methane....

  • Could it be possible that there was life on mars... and not any more? Those long dead critters are continuing to decay and release the gas.

    • Re:Is it possible? (Score:4, Interesting)

      by Narcocide (102829) on Tuesday December 08, 2009 @04:11PM (#30370376) Homepage

      Yes and I think it is also theoretically possible that there was life on mars until about half an hour after the first probe landed.

    • Life on Mars would have been at its prime billions of years ago. Whatever is left now would have to be either fossilised and completely inert, or still reproducing.
      • Re: (Score:3, Insightful)

        by H0p313ss (811249)

        Life on Mars would have been at its prime billions of years ago. Whatever is left now would have to be either fossilised and completely inert, or still reproducing.

        Or migrated?

    • Re:Is it possible? (Score:5, Insightful)

      by Orleron (835910) on Tuesday December 08, 2009 @04:36PM (#30370676) Homepage
      "Decay" implies the breakdown of biological tissue by... you guessed it, micro-organisms. In places where there is not much bacteria, like the antarctic, things that die do not decay noticeably over hundreds of years or more.
      So, I doubt decay from dead things is producing the methane.
    • by vlm (69642)

      Could it be possible that there was life on mars... and not any more? Those long dead critters are continuing to decay and release the gas.

      Coal, Oil wells, and NatGas wells are basically the same thing. If those deposits existed on mars, King Bush II and Haliburton would have been invading Mars for Oil rather than mostly innocent middle eastern countries for Oil. Therefore, theres no hydrocarbon fields on Mars. So, if the methane isn't from fossils, its from modern/current critters...

      Methane is unstable on the order of centuries in the martian atmosphere, so they all died off VERY recently, not so "long dead" as you might think.

    • by Java Pimp (98454)

      Actually, decay is caused by living microbes breaking down the organic matter (and releasing methane). No life means no decay (in the metabolizing sense). Dead organic matter with nothing to cause decay would likely dry up and turn to dust or become fossilized.

  • option C (Score:5, Insightful)

    by kingmundi (54911) on Tuesday December 08, 2009 @04:01PM (#30370224)

    "So two theories remain: either the gas is created as a by-product of reactions between volcanic rock and water, or it is a by-product of a lifeform's metabolism."

    Or C: There is some, as of yet, unidentified method of methane production.

    • by Spatial (1235392)
      Undefined methods aren't "theories" you smartass.
      • by SomeJoel (1061138)

        Undefined methods aren't "theories" you smartass.

        Well, not yet they aren't. But I assume once the methods become identified (or "defined") they will spawn new theories.

        The phrase "So two theories remain" strongly implies that these are the only two possible causes, when really there are probably others.

      • Re: (Score:3, Insightful)

        by kingmundi (54911)

        I probably should have put...
        there are probably other theories out there besides those two. And its always important to keep an open mind to other possibilities.

        Personally, I tend to favour the water interacting with olivine (serpentization). The two main plumes of methane occur at points in Mars where there are cracks to the interior, and/or have a lot of exposed olivine. Of course, I am not a scientist, so I don't even give my own opinion much weight on the matter. Its possible that the presence of ol

    • "So two theories remain: either the gas is created as a by-product of reactions between volcanic rock and water, or it is a by-product of a lifeform's metabolism."

      Or C: There is some, as of yet, unidentified method of methane production.

      That's not a theory, it's a catch all.

    • Re: (Score:2, Troll)

      by jpmorgan (517966)

      If only the IPCC members had such depth of insight.

    • "So two theories remain: either the gas is created as a by-product of reactions between volcanic rock and water, or it is a by-product of a lifeform's metabolism."

      Or C: There is some, as of yet, unidentified method of methane production.

      Taco Bell?

  • It makes enough methane for the whole planet, that's for sure.

  • Overlords (Score:2, Funny)

    by Anonymous Coward

    I, for one, welcome our new flatulent Martian overlords.

  • There's a small worm hole from the local Taco Bell leading to Mars.
  • by Knara (9377) on Tuesday December 08, 2009 @04:25PM (#30370546)
    Who knows, it could just be a piece of pre-animate matter caught in the matrix.
  • Back in March, there was an article in "Nature News" [nature.com](the Nature News article is subscription, but a decent summary was posted by "The Free Republic" [209.157.64.200]) that the mineral Olivine when incorporated in a hydrothermal system may generate methane.

    On Earth, the predominate source of methane is considered biological in origin, and the presence on Mars has been considered a possible indication of life on Mars. Recently, at the Lunar and Planetary Science Conference at The Woodlands, near Houston, Texas, researcher
  • Cows (Score:5, Funny)

    by JustNiz (692889) on Tuesday December 08, 2009 @04:39PM (#30370724)

    Cows ruined their own planet before they came to earth millenia ago.
    Its this migration that the child's nursery rhyme is referencing in the line "the cow jumped over the moon".
    They're now doing the same to the earth.

  • by khallow (566160) on Tuesday December 08, 2009 @04:43PM (#30370766)
    As I understand it, we know there's olivine on Mars [hawaii.edu] and that there's water on Mars [timesonline.co.uk]. Assuming the laws of physics operate the same on Mars as on Earth, then you have all the explanation you need for methane on Mars. Serpentinization [wikipedia.org] is the process of reacting olivine with water. It generates methane as a byproduct.

    The question isn't whether serpentinization is a source of methane, but rather whether it is the majority source or not. My take is that if the methane production was due to life on Mars, there'd be a lot more methane being produced than a few hundred tons a day. I don't see life on Mars staying in one place over millions much less hundreds of millions of years. But I suppose there's a chance it could happen that way (say if life on Mars is a relatively recent phenoma).
    • by H0p313ss (811249)

      But I suppose there's a chance it could happen that way (say if life on Mars is a relatively recent phenoma).

      Like, say for example, a recent visit from an alien probe managed to infect it with lifeforms from another planet? But who would send probes to mars? Must ponder that...

    • I can imagine a situation analogous to deep sea vents, where you get "hot spots", or perhaps in the case of Mars, places where energy is plentiful enough to sustain ecosystems. In either case, the further you get away from such areas of accessible energy and resources, life becomes more sparse. It's also possible that Mars' harsher environment means organisms tend to metabolize much slower (we see this with organisms found deep below the surface).

      It would be interesting, in the case of Earth, to figure ou

    • Re: (Score:3, Interesting)

      by mbone (558574)

      Several troubles with that idea. First, note that the Methane production rates quoted in the original article are much too small based on the observed Martian Methane plumes and their implications. Given that

      - it's hard to see how serpentinization explains the observed intermittent methane plumes

      - it doesn't explain at all the sink of the methane, which has to be very powerful (to explain the observed plumes)

      - the production estimates by Lefèvre & Forget [nature.com] (Nature 460, 720-723 (6 August 2009)) are

  • Sounds a bit like the "God in the Gaps" line of reasoning. Well, to be fair, "lifeform creates methane" is testable and all ready been shown true on Earth. I guess I'm just cranky after debugging all night...

    Wow, I almost wrote "to be fair", imagine the flame fest that would have started. What can I say, my fingers type the first word that matches phonically.

  • How is it possible for there to be methane on Mars, yet it's a cold as ice. You FAIL Al Gore!
  • Go ahead (Score:4, Funny)

    by PPH (736903) on Tuesday December 08, 2009 @05:29PM (#30371380)

    Pull my tentacle.

  • by mbone (558574) on Tuesday December 08, 2009 @08:10PM (#30372928)

    Neither the source nor the sink of Martian methane is understood, as was discussed by Lefèvre & Forget in Observed variations of methane on Mars unexplained by known atmospheric chemistry and physics [nature.com] (Nature 460, 720-723 (6 August 2009)). Unlike the statement in the spacefellowship.com writeup, the observed methane plumes require a very quick absorption of methane on the surface, which means that the lifetime of methane in the atmosphere is not " a few hundred years" but months or less, maybe even hours or less. Since the shorter the lifetime, the larger the production required to match the observed plumes, we don't know the methane production on Mars to within even 3 orders of magnitude.

    We don't know the source, we don't know the sink, and we don't know the production rate, so I personally don't see how biology can be ruled out, despite the editorializing in Lefèvre & Forget.

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