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NASA Space Science

Hints of Life Found On Saturn's Moon Titan 227

Calopteryx writes "New Scientist reports that in 2005, researchers predicted two potential signatures of life on Titan. Now, thanks to research done with the help of the Cassini spacecraft, both have been seen, although non-biological chemical reactions could also be behind the observations. NASA's writeup has further details: 'One key finding comes from a paper online now in the journal Icarus [abstract] that shows hydrogen molecules flowing down through Titan's atmosphere and disappearing at the surface. Another paper online now in the Journal of Geophysical Research maps hydrocarbons on the Titan surface and finds a lack of acetylene. This lack of acetylene is important because that chemical would likely be the best energy source for a methane-based life on Titan, said Chris McKay, an astrobiologist at NASA Ames Research Center, Moffett Field, Calif., who proposed a set of conditions necessary for this kind of methane-based life on Titan in 2005. One interpretation of the acetylene data is that the hydrocarbon is being consumed as food. But McKay said the flow of hydrogen is even more critical because all of their proposed mechanisms involved the consumption of hydrogen.'"
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Hints of Life Found On Saturn's Moon Titan

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  • NASA routinely crashes its space probes after their extended missions to prevent any sort of contamination to possible life forms indigenous to the celestial bodies in the area.

    I wonder if the Huygens probe's plunge to the surface may have introduced contaminants to Titan's "biosphere".

    That would kind of suck. And now we'll never know, since future visits could very well detect readings caused/contaminated by Huygens.
    • Re: (Score:2, Informative)

      by Anonymous Coward

      It sounded like it was referring to heretofore unknown kinds of life that use completely different chemical processes than we see on earth, with the possible exception of really weird stuff that you find at the bottom of the ocean. Nothing that would have gotten onto our probe, in any case.

    • by dreamchaser ( 49529 ) on Friday June 04, 2010 @01:17PM (#32461268) Homepage Journal

      I think you misunderstand. The mechanisms that would cause life to consume the substances that are 'missing' are totally alien to life as we know it, but fit the model for methane based life very well. It could well be that there are non-biological chemical processes doing it, but the odds of it being from any contamination from Huygens is astronomically remote. Hugyens was also very, very carefully sterilized. Granted, a microbe or two might have made it to Titan, where it would most likely die rather than reproduce.

      I do see your point and we need to continue to be careful, but I see nothing in these findings that makes the Hugyens discussion at all relevant to this story.

      • by infinitelink ( 963279 ) on Friday June 04, 2010 @07:36PM (#32465806) Homepage Journal
        Actually I don't think his is a bad point. First off, we DON'T understand the metabolisms of most microbes on earth: most CAN'T be cultured in a lab because of this, experimented with, etc. etc.: only a little subset of the entire known microbial biota are even available for us to research. Beyond this, however, the known range of things that microbes can eat is expanding beyond our wildest imaginings: and not just on the bottom of oceans. That's why we now have microbes to use to eat oil spills, nuclear waste, and even metals (ummm....iron and steal, yum!). Not kidding about the bacteria that eat metals, by the way, which incidentally...DO IT BY HYDROGEN AND ELECTRON EXCHANGES. There's all sorts of stuff that one can tell you haven't even considered from the comment you just made: you need to do more dreaming "dream[er]...".

        P.S. bacteria have survived in the vaccum of space on the moon, so "[they] would most likely die" is also not a very informed statement. I don't mean to be too insulting here, just very frank about the state of knowledge on these things vs. what you wrote: that is rose to "5, Insightful" just demanded the bio nerd in me to respond.
    • by sznupi ( 719324 )

      Not only the impact of Huygens or any future probe [wikipedia.org] would be miniscule - with certainly quite different chemistries of Earth life and any possible Titan life, plus with very precise list of probe components and "payload", there should be little chance of confusion...

      • Re: (Score:3, Informative)

        I have a pretty good suspicion that most life on Earth, even the extremophiles, would have a rather hard time living on Titan. The temperatures are extremely low, the solar energy and even Saturn's energy are much less combined than on Earth. The kind of biochemistry would be quite different than found here. I'm not saying it's entirely impossible, but I think a planet like Mars would be far more likely to be able to harbor certain hardy organisms from Earth than a place like Titan. My understanding is

        • by sznupi ( 719324 )

          Yup. And BTW the "seas" (lakes?) on Titan seem to be methane-ethane; so that's probably the main solvent. I think we use comparable chemicals for very low level disinfection...

    • I must be misinterpreting your comment. Can you explain how crashing a probe into a celestial body has LESS contamination risk than just letting it drift off into the void?
      • by Binestar ( 28861 )
        Carrying enough propellant to escape orbit again is much heavier than carrying enough to crash into something with gravity assist.
      • Re: (Score:3, Funny)

        by owlstead ( 636356 )

        Easy, drifting anything into the void contaminates the void.

      • by IndustrialComplex ( 975015 ) on Friday June 04, 2010 @03:01PM (#32462918)

        I must be misinterpreting your comment. Can you explain how crashing a probe into a celestial body has LESS contamination risk than just letting it drift off into the void?

        Generally, they crash it into a celestial body that has no capability to support life and, such as the case of Jupiter, is hostile to the biological processes of what could possibly contaminate it.

        No life from Earth will survive in Jupiter's atmosphere. The pressure is... extreme beyond that of the extreme on Earth.

        The pressure there would be 10,000 times greater than the pressure at the deepest point in Earth's ocean. 10,000,000 Earth Atmospheres compared to 1,000 in the Marianas Trench.

        Then you have the temperature. The hottest spot on Earth (the core) is about 7300K. On the liquid 'surface' of Jupiter, it is 10,000k. The most extreme of the thermophiles on Earth live in an area less than 400k. The core of Jupiter is hotter than the surface of the Sun.

        If you find me something that can survive 10,000k temperatures and 10 million atmospheres I'd bow down to my new overlord.
         

    • Re: (Score:3, Insightful)

      It would be fairly easy to tell earth based contamination from native stuff. For starters, I'm not aware of any bacterium that you would find on the surface of the earth that eats hydrocarbons in that way and can live in those conditions. Below the artic ice? maybe... but in a clean room in texas? not likely.

    • by Vekseid ( 1528215 ) on Friday June 04, 2010 @01:32PM (#32461490) Homepage

      Breathing hydrogen basically works in the opposite direction of terrestrial biochemistry. The proposed organisms are breathing hydrogen and presumably fixing it to something (say, oxides they've eaten) rather than the other way around as for Earth life.

      And even if it was possible, Huygens could not have contaminated things to such a degree as to affect widespread atmospheric phenomenon.

    • Re: (Score:3, Informative)

      by sunspot42 ( 455706 )

      The probe was sterilized, if I recall correctly. So it shouldn't be an issue.

      Keep in mind that in the long history of the solar system it's likely that material blasted off the earth by an impact event or events has made its way to the surface of Titan. So Titan may have already been contaminated with life from earth.

    • by radtea ( 464814 )

      I wonder if NASA has been routinely sterilizing soft landers for decades to avoid exactly the kind of thing you are wondering about.

      I wonder if it might be possible to tell the difference between Earth-based contaminants and indigenous lifeforms by biochemical and (in the extremely improbable case of biochemical similarity) genetic analysis.

      I wonder if it's possible to post questions on /. without knowing the first thing about a topic.

      I wonder what I'll have for dinner.

      I wonder where my socks are.

      • As someone who works for a company that subcontracts planetary instruments to NASA, the requirements im posed by NASA that you have to follow to prevent contamination are extreme to say the least.

      • by Plekto ( 1018050 )

        The main reason they sterilize their probes is to get "cleaner" data and no risk of contamination of future probe readings. After all, one cell is all they need to find. Any false-positive will be a disaster that they'd never live down.

        • Re: (Score:3, Interesting)

          by DM9290 ( 797337 )

          The main reason they sterilize their probes is to get "cleaner" data and no risk of contamination of future probe readings. After all, one cell is all they need to find. Any false-positive will be a disaster that they'd never live down.

          not to mention contaminating other components of the same probe.

          at least the discovery that earth life flourished on a celestial body would be scientifically interesting. A space probe that did nothing but detect that it was self-contaminated prior to launch and can't provide useful data would be a total failure.

  • by MediaCastleX ( 1799990 ) on Friday June 04, 2010 @01:07PM (#32461128) Journal
    When I was in Jr. High, my science class had an assignment where we had to make-up a life form, based on the planet chosen's conditions and mine was Saturn. Of course my design was completely ridiculous, but the idea was pretty much close to what they're saying about Hydrogen consumption. This is pretty cool...I *heart* Saturn. "Pro'lly 'cuz it gots money with all them rings it has!" lol =P
  • Those Titanians are constantly drunk. That's probably very smart as long as they don't drive.

  • by elrous0 ( 869638 ) * on Friday June 04, 2010 @01:10PM (#32461164)
    ...or possibly not.
  • Oh jeez (Score:5, Insightful)

    by Some.Net(Guy) ( 1733146 ) on Friday June 04, 2010 @01:10PM (#32461166) Homepage
    The worst thing that could possibly happen for any form of life anywhere would be its discovery by us.
    • Re: (Score:2, Insightful)

      by elrous0 ( 869638 ) *
      Nonense. If it weren't for us, many species (that probably deserve to) would probably have already went extinct. Does anyone think the Pandas would still be around if we weren't constantly working to try to get them to mate? It's taken more effort to get those things to reproduce than it took with Tom Cruise, for crying out loud. Seriously, if your species needs Viagra to stay viable, it's probably nature's way of saying your species just wasn't meant to be.
      • Re: (Score:2, Funny)

        by somersault ( 912633 )

        Well I don't know about you, but I probably wouldn't like being locked up and forced to have sex with some ugly fat chick..

      • Re: (Score:2, Insightful)

        by Locke2005 ( 849178 )
        Sure, their reduction in number couldn't possibly have anything to do with the vast reduction in habitat caused by human activity! And their lack of hetero sex drive couldn't possibly be due to stresses caused by overcrowding and human activity, so siree! Just because pandas survived for millions of years before humans became so numerous in their vicinity doesn't imply any causal relationship between their precipitous decline and the corresponding rise in human population, it is obviously due to the fact th
      • Please tell me you're being funny and are only pretending to be clueless as to how these species ended up in the situations that required us to save them.

      • Re:Oh jeez (Score:4, Insightful)

        by sznupi ( 719324 ) on Friday June 04, 2010 @01:58PM (#32461924) Homepage

        We're in the middle of one of the most rapid extinction events in the history of this planet, generally speaking.

        Accidentally, it kicked in when we really got the hang of the place...

        • Sounds like humanity is a bit of drunk football team crashing your place for a party. Once they know where the fridge is, and once it's empty, it suddenly ends up in the pool.
      • Nonense. If it weren't for us, many species (that probably deserve to) would probably have already went extinct.

        Tell that to the Japanese Wolf, the Bali tiger, the North African Elephant and the hundreds of other species that went extinct due to mans' interference.

    • Especially if they are sitting on top of "exploitable resources".
    • by Reapman ( 740286 )

      Insightful? I know we seem rather big and important to you.. but honestly, we're not (on universe or "anywhere") type scale. Assuming for a moment that other life forms even exist out there, and assuming that there are some at various stages of development, you REALLY TRULY can not think of anything worse then Humans?

      I don't think we're as special.. either in a good way or a bad way.. as you think we are.

    • Only if we decide its OK to eat them.
    • Depends. Maybe they are more like us, than we ourselves are. ;)
      Maybe we are very tasty and/or a easily harvestable resource to them.

  • by sznupi ( 719324 ) on Friday June 04, 2010 @01:13PM (#32461202) Homepage

    http://en.wikipedia.org/wiki/Titan_Mare_Explorer [wikipedia.org] (hopefully not postponed to be part of http://en.wikipedia.org/wiki/Titan_Saturn_System_Mission [wikipedia.org] )

    Titan, and Saturn system generally, is a really big thing for our distant future. People like to imagine the colonisation of Jupiter system, but the radiation belts there make it not exactly feasible; only Callisto out of 4 big moons might be fine. Saturn doesn't have this problem; is still decently close and with huge system of moons.
    Discovery of life on Titan might of course complicate things...OTOH, with it (if any) being probably so vastly different, there's little risk of crosscontamination in either direction.

    • Titan, however, has the problem of being damned cold. I don't think it's a given that radiation is harder to deal with than that amount of greenhouse engineering.
      • by sznupi ( 719324 )

        That is its only major problem though (well, that and the atmosphere being highly toxic to humans - essentially with the addition of...Zyklon B). Other than that it offers protection, stability of conditions, "zero pressure difference" (ok, you would probably want to maintain a slight overpressure inside the base, due to toxicity - together with the cold outside that might make any leaks largely self-closing); greatly simplifying things compared to many other places, so you can concentrate easily on thermal

    • Knowing our luck, we're going to just crash some crap into Titan, either killing off whatever lives there or starting a war with it.
  • Come on. This is so weak and wrong. Now if you excuse me I'm going to go make myself a hydrogen and acetylene sandwich.

    • Occam's razor suggests that the simplest solution is usually the correct one. It does NOT mean "Reject a hypothesis because someone thinks it's not simple enough." Is there an obvious, simpler hypothesis that I'm not seeing?

      Actually it doesn't matter. You test hypotheses, you don't just misuse occam's razor to assume one is right. We'll be sending another probe to Titan eventually and that will settle it.

  • Attempt no landings there, either.
  • by by (1706743) ( 1706744 ) on Friday June 04, 2010 @01:22PM (#32461338)
    I, for one welco...ah, screw it.
  • I seem to remember a movie, also, something about a computer run amok and life on one of the moons near Saturn... ...or was it Jupiter?
  • Giant Laboratory (Score:3, Interesting)

    by pankajmay ( 1559865 ) on Friday June 04, 2010 @02:28PM (#32462416)
    Titan is a young celestial body - with its own dense atmosphere and the only body until now in the solar system that has surface liquids apart from us.

    Sure it can be hypothesized that since Titan is young - it probably is taking a course that Earth took millions of years ago. With the distance from Sun rendering it cold and the fact that it orbits Saturn being the primary differences.

    Of course finding Life would be an enormous discovery. But if we start with what we already know - that Organic reactions are taking place on Titan's surface, and that it is a giant Organic Soup -- It gives us a huge interesting laboratory to study and experiment!

    We can even direct Titan's course of life by controlled introduction of earth's anaerobic life on its surface -- since we already know a hypothesis on how our own Earth's atmosphere has evolved into the current air composition -- we can *test* and use those theories to change Titan's atmosphere, in turn not only validating our theories, but may be making Titan inhabitable like Earth!

    Exciting to say the least! If only we humans can, just for a second -- stop bickering amongst ourselves and look outwards to this possibility!!

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