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Methane-Based Life Possible On Titan

Posted by Soulskill on from the it's-life-jim-but-not-as-we-know dept.

Randym writes: With the simultaneous announcement of a possible nitrogen-based, cell-like structure allowing life outside the "liquid water zone" (but within a methane atmosphere) announced by researchers at Cornell (academic paper) and the mystery of fluctuating methane levels on Mars raising the possibility of methane-respiring life, there now exists the possibility of a whole new branch of the tree of life that does not rely on either carbon or oxygen for respiration. We may find evidence of such life here on Earth down in the mantle where "traditional" life cannot survive, but where bacteria has evolved to live off hydrocarbons like methane and benzene.

15 of 69 comments (clear)

  1. membrane by itzly · · Score: 3, Interesting

    Making a shell is nice, but that's hardly the most fundamental aspect of life.

    1. Re:membrane by ColdWetDog · · Score: 3, Insightful

      Sure it is. That's how you concentrate things. Probably wasn't the first thing life did - replication has to happen first, but it was an early (and energetically favorable) change.

      --
      Faster! Faster! Faster would be better!
    2. Re:membrane by circletimessquare · · Score: 2

      making a micelle was the very first step in creating life

      http://en.wikipedia.org/wiki/P...

      the next step was the chemicals concentrated in the micelle being able to control it

      --
      intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
    3. Re:membrane by itzly · · Score: 2

      Making a bag is much simpler than making a self-replicator. I don't know about you, but when I try to figure out if something is possible, I start with the hardest part.

    4. Re:membrane by circletimessquare · · Score: 2

      go pour a little soap/oil in some water and shake it

      congratulations, you've "made" micelles

      micelles are self organizing. you don't "make" sea foam, it's a simple product of natural wind and wave with sufficient chained carbon compounds

      micelles occurred naturally in the early earth out of non organic processes that produced simple hydrocarbons

      then the rudmientary self-replicating processes also occuring naturally in that time period, and sputtering out, uncontained, joined up with micelles and sustained. because now they have a safe container to continue in

      thus the first cell, from which all the rest has sprung

      --
      intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
  2. Oxygen-based life possible on Earth by Anonymous Coward · · Score: 5, Insightful

    Although the third planet from the Sun suffers from crippling gravity and heat, scientists long held that the corrosive atmosphere of oxygen and water vapor is what forbids life as we know it.

    If we didn't melt instantly from the heat or collapse from the gravity, the oxygen would burn us up in a flash! Scientists have been unable to explain how so much uncombined oxygen could exist in the atmosphere of such a hot planet, but new data suggests life *is* possible with a carbon-based shell of special molecules called lipids and proteins.

    etc... etc.. etc...

    1. Re:Oxygen-based life possible on Earth by Applehu+Akbar · · Score: 2

      I've seen their VHF transmissions about their god "Hank Hill"! If those fiery demons ever come to our Titan, they would drill wells for water, contaminating other methane and ethane we breathe.

    2. Re:Oxygen-based life possible on Earth by dotancohen · · Score: 2

      Although the third planet from the Sun suffers from crippling gravity and heat, scientists long held that the corrosive atmosphere of oxygen and water vapor is what forbids life as we know it.

      Discussed on Stack Exchange:
      http://worldbuilding.stackexch...

      --
      It is dangerous to be right when the government is wrong.
  3. Doesn't rely on carbon or oxygen? by ShadowRangerRIT · · Score: 3, Insightful

    Methane is CH4. The C is for carbon. Come on people!

    --
    $_ = "wftedskaebjgdpjgidbsmnjgcdwatb"; tr/a-z/oh, turtleneck Phrase Jar!/; print
    1. Re:Doesn't rely on carbon or oxygen? by meglon · · Score: 2

      That kind of stumped me too; if it's replacing O2 with methane for respiration, that line really makes no sense. I put it down as the summary writer mistaken a phrase in the article as saying the cells were nitrogen bases, as opposed to carbon based... which isn't actually what the article says.

      That said, the idea of using a different base for respiration doesn't really require much imagination. We use oxygen because that's the environment we evolved in; any life evolving in an atmosphere without oxygen will use something else. Even advanced life forms could use non-oxygen molecules for respiration, the only requirement being that whatever their circulatory system used could bind with, and carry, the molecule (making the very limiting assumption that their system would work similar to ours).

      We have on our planet microbes that do not respirate oxygen, and are in fact killed by an oxygen atmosphere. Our advanced oxygen breathers are not even limited to a single carrying element. Sure, the land O2 users have iron based blood, but there is O2 "breathing" sea life that has copper based blood (and no, it's not green.... Roddenberry got that wrong), and others with a copper/vanadium hybrid based blood (which is green, but a bright yellow green).

      Life will use what's available; no oxygen... probably not problem.

      --
      Fascism: An authoritarian and nationalistic right-wing system of government and social organization. See also: NAZI's
    2. Re:Doesn't rely on carbon or oxygen? by theVarangian · · Score: 2

      Methane is CH4. The C is for carbon. Come on people!

      You left out the last part: "...does not rely on either carbon or oxygen for respiration". I'm no chemist nor am I an expert in exobiology so somebody who is may feel free to educate me if I' wrong here. Having said that, the way I understand it a hypothetical methane based life form on Titan would use complex hydrocarbons as an energy source by reacting them with hydrogen like for example reducing ethane and acetylene to methane and it would consume i.e. respire (inhale) hydrogen for that purpose. So the statement is correct, these Titanian life forms would neither respire (inhale) Oxygen nor a carbon based gas like life forms on earth do, just the hydrogen that is disappearing when it hits the surface of Titan. What you would expect to seen if such life forms existed on Titan. would be an unexplained disappearance of hydrogen (check) and methane being produced (check) with fluctuations in both as populations of these life forms grew and shrank for whatever reasons (seasons, radiation, predators, ...???). Of course there are other ways of explaining such fluctuations which is why we must send a rover to Titan a.s.a.p to do some research.

  4. Re:No. It's not. by ColdWetDog · · Score: 2

    Why aren't you feeding the poor instead of posting on Slashdot? Isn't that the most important thing? You could have given some well deserved, undernourished child one of your twinkies. Oh wait, the child lives in some stinking desert without a functioning water well in five miles.

    Or maybe we could use some of the earth sensing satellites (created by those self same hair-brains) to map out artesian flows and show people on the ground where an inexpensive well could be dug. Or we could give the kid a vaccine (developed by that same complex and expensive infrastructure created by those hair-brains) to keep him healthy so he can go to school and break out of the cycle of fear, anger and misuse that characterizes his world.

    Or perhaps not - the world is a complex and often ugly place. Quite a bit more complex than your apparent world view, I won't comment on whether or not your view is particularly unattractive but I'm damned sure glad I don't feel that way.

    --
    Faster! Faster! Faster would be better!
  5. Exclusive: pix of Titan ancient civilizations by youn · · Score: 2

    According to a news flash I just made up, NASA sent a probe to titan and not only found definitive proof of life there but they were able to take pictures of ancient civilizations of methane based life on titan... According to a new hypothesis formulated by the lead scientist on the mission, "This must be some very old fart" :p

    --
    Never antropomorphize computers, they do not like that :p
  6. Re:based vs inhaling vs exhaling by Immerman · · Score: 5, Informative

    Slashdot summaries are confused, when not outright inaccurate - news at 11. If you actually want to know details, you're pretty much required to RTFA.

    As for your question, humans (/mammals/animals/multicellular organisms) are a recent addition, not typical of Earth-based life.

    Earth life is water-based (well, suspended anyway), with lipid(hydrocarbon)-based cell walls to keep vital chemistry sufficiently concentrated to continue. Eventually blue-green algae evolved their ability to photosynthesize and poisoned the planet with toxic oxygen byproducts, which some of the survivors later managed to harness as a fuel. But that's really an incidental development so far as life itself is concerned. Before that life was all chemovores - likely consuming complex organic molecules from either hydrothermal vents and/or their fellows for both nutrients and energy.

    In this case researchers have found some other hydrocarbons that can form "cell walls" with properties very similar to those in our own cells, except that they operate in a liquid methane suspension instead of water, at temperatures that would render our own cell walls solid. One of those hydrocarbons is acrylonitrile, a compound found in Titan's atmosphere, so the building blocks for cell walls at least are already present there.

    --
    --- Most topics have many sides worth arguing, allow me to take one opposite you.
  7. Titan is a most beautiful moon by xororand · · Score: 2

    Titan is gorgeous.

    https://upload.wikimedia.org/w...
    http://www.astrobio.net/wp-con...
    True color: https://upload.wikimedia.org/w...

    It's also the setting of the first chapter in the brilliant hard sci-fi novel Fiasco by Stanislaw Lem.
    I can't wait for new probes to report from there.