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Hydrocarbon Rain Swells Titan's Lakes

Posted by kdawson on from the singin'-in-the-methane dept.

Rob Carr writes "According to the Cassini team, 'Recent images of Titan from NASA's Cassini spacecraft affirm the presence of lakes of liquid hydrocarbons by capturing changes in the lakes brought on by rainfall.' The northern lakes are now larger following a period in which hydrocarbon clouds covered their skies. (The research was published in the journal Geophysical Research Letters.) This change adds to the evidence these areas are indeed hydrocarbon lakes. But this discovery raises several more questions: where is the methane in the atmosphere coming from, and how long can this complex hydrocarbon cycle on Titan go on? The new evidence emphasizes the need for another mission to Titan."

10 of 110 comments (clear)

  1. Nothing New ! by AmigaMMC · · Score: 4, Interesting

    I had already read that in Stephen Baxter's novel "Titan" - That guy is always so right! :)

  2. source http://www.esa.int by Saysys · · Score: 5, Interesting

    The question of how much liquid is on the surface is an important one because methane is a strong greenhouse gas on Titan as well as on Earth, but there is much more of it on Titan. If all the observed liquid on Titan is methane, it would only last a few million years, because as methane escapes into Titan's atmosphere, it breaks down and escapes into space.

    If the methane were to run out, Titan could become much colder. Scientists believe that methane might be supplied to the atmosphere by venting from the interior in cryovolcanic eruptions. If so, the amount of methane, and the temperature on Titan, may have fluctuated dramatically in Titan's past.

    1. Re:source http://www.esa.int by ogdenk · · Score: 3, Interesting

      it would only last a few million years, because as methane escapes into Titan's atmosphere, it breaks down and escapes into space.

      Does that suggest that Titan itself is rather young compared to the planet it orbits? Or was Titan much more active and possibly larger 50 million years ago?

      I'm not a geologist or astrophysicist so I'm rather ignorant in this department.

  3. Abiogenic Hydrocarbons by PPH · · Score: 3, Interesting

    The question of where all of Titan's hydrocarbons come from might cause the theory of abiogenic petroleum to be revisited. Much to the chagrin of the peak oil proponents.

    --
    Have gnu, will travel.
  4. Wouldn't it be crazy... by Metasquares · · Score: 2, Interesting

    If there were life on Titan using hydrocarbons as we use water?

    I'm sure there are several reasons why this is chemically infeasible, but I just wanted to throw the possibility out there. We tend to get into bad habits of assuming that extraterrestrial life would function just as terrestrial life would.

    1. Re:Wouldn't it be crazy... by Rob+Carr · · Score: 3, Interesting
      I did a calculation a while back, assuming that the rule of thumb on earth held on Titan: reaction rates drop 50% for 10 degree drop in temperature. Using an estimate for the time required to develop life on Earth, the calc indicated it would be unlikely to have developed on Titan within the lifetime of the universe.

      Of course, there are quite a few problems with that analysis:
      1. Different chemical system might make the reaction rate different.
      2. That's a long way to push a law that obviously fails at the freezing temp of water.
      3. If life formed on Earth much sooner than the estimate I used, again the number might be off.

      Then again, what would be the information molecule? DNA is a polymer with subunits that can encode information. There aren't a lot of methane-soluble polymers that would make for good information storage.

      Then again, maybe I'm not thinking outside the box and something radically different would be used.

      Life on Titan is unlikely, but I think we'd be making a big mistake assuming it's impossible.

      --
      This sig seemed like a good idea at the time....
  5. Re:Space Oil Tanker... by NeverVotedBush · · Score: 3, Interesting

    I'm wondering how you land all that methane back on earth.

    It may be a liquid on Titan, but as you get it back closer to earth and let the sun start to warm the skin of the spaceship, it's going to start turning into gas and take up a lot more volume.

    But let's assume you figure out a way to keep it liquid. How do you get it back down to earth? A space shuttle sized spacecraft is only going to be able to bring back a tanker truckload or so. You'll use much more energy than that just to relaunch some spacecraft to go get more.

    It's a terrible idea anyway, but also impractical.

  6. Re:Now all we need... by jmv · · Score: 2, Interesting

    The funny thing is that doing that might cause global cooling because CO2 is much less effective at trapping heat than methane.

    --
    Opus: the Swiss army knife of audio codec
  7. Re:Now all we need... by MichaelSmith · · Score: 2, Interesting

    Yes I though about that. CO2 will actually have zero warming effect because it is a solid at Titan surface temperatures. Environmentalists may complain about carbon fog.

    --
    http://michaelsmith.id.au
  8. Re:Obvious source of the methane... by TheCybernator · · Score: 2, Interesting

    HydroCarbons and Titan and only one Uranus joke? it must be Sunday today!

    --
    Eclipse PDE and Me