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Craters Quickly Hidden On Titan

MightyMartian writes "NASA scientists say Cassini has discovered that far fewer craters are visible on Titan than on the other moons of Saturn. The craters they have discovered are far shallower than other moons' craters and appear to be filling with hydrocarbon sand. On top of being another reason Titan's active geology is very cool, it adds to the mystery of where all the methane on Titan is coming from. 'The rain that falls from Titan's skies is not water, but contains liquid methane and ethane, compounds that are gases at Earth's temperatures. ... The source of Titan's methane remains a mystery because methane in the atmosphere is broken down over relatively short time scales by sunlight. Fragments of methane molecules then recombine into more complex hydrocarbons in the upper atmosphere, forming a thick, orange smog that hides the surface from view. Some of the larger particles eventually rain out onto the surface, where they appear to get bound together to form the sand.'"

39 comments

  1. Titan's active geology is very cool by MichaelSmith · · Score: 1

    cool

    About 90 kelvins, right? Its only twice as cold as the coldest place on Earth, relative to normal Earth temperatures.

    1. Re:Titan's active geology is very cool by MichaelSmith · · Score: 2

      The source of Titan's methane remains a mystery because methane in the atmosphere is broken down over relatively short time scales by sunlight

      Hang on a minute: wasn't free methane being used as an indicator of life on Mars? So where does this methane come from?

    2. Re:Titan's active geology is very cool by Anonymous Coward · · Score: 1

      Cows produce methane. Isn't it obvious?

    3. Re:Titan's active geology is very cool by ThePeices · · Score: 4, Insightful

      The source of Titan's methane remains a mystery because methane in the atmosphere is broken down over relatively short time scales by sunlight

      Hang on a minute: wasn't free methane being used as an indicator of life on Mars? So where does this methane come from?

      Kind of. Methane could be generated on Mars either by biological means, or by geological means.

      If its geological, then the sub-surface of Mars is more active than we thought.
      If its biological in origin, well there's the biggest discovery in human history right there.

      For the record, im guessing geological.

    4. Re:Titan's active geology is very cool by Anonymous Coward · · Score: 0

      "Raining Ethane" = free booze from heaven, just add water.

    5. Re:Titan's active geology is very cool by Anonymous Coward · · Score: 0

      Ethane =/= ethanol, but it's close enough that any childrens chemistry set will be able to convert it easily.

    6. Re:Titan's active geology is very cool by dkleinsc · · Score: 1

      So where does this methane come from?

      Sorry, that was me.

      --
      I am officially gone from /. Long live http://www.soylentnews.com/
    7. Re:Titan's active geology is very cool by Anonymous Coward · · Score: 1

      Ok, then tell us how you would convert ethane into ethanol using a children's chemistry set in usable yields, dear AC.

      As they say: put up or shut up.

      BTW: I am a chemist and this transformation is certainly not trivial, because ethane has no functional groups and therefore you would need quite harsh conditions. Not something to find in your run-of-the-mill nursery. This is not even considering getting sensible yields.

    8. Re:Titan's active geology is very cool by AndyKron · · Score: 1

      If you go, don't forget your mittens!

    9. Re:Titan's active geology is very cool by Anonymous Coward · · Score: 1

      It's trivially converted by partial hydrolysis under high vacuum or, if you want to avoid the vacuum pump (which isn't part of kids chemistry sets), you could react the ethane to ethene and then enzymatically go to ethanol. Then it's just seperating the product by distilling.

      A quick back-of-the-envelope guesstimate gives a yield of about twenty percent. Which isn't much, but when you have an entire planet full of ethane you can afford some loss.

    10. Re:Titan's active geology is very cool by Anonymous Coward · · Score: 0

      Dehydrogenation of ethane to ethylene and a subsequent bio-synthesis all using a children's chemistry set!? LOL! Clearly your only experience with chemistry is on paper. If you're going the bio-route, just ferment some good old sugar and be done with it.

    11. Re:Titan's active geology is very cool by Anonymous Coward · · Score: 0

      The article does not mention any sugar found on Titan, so that might be a snag in your plan.

      And I'm not sure why you think the above mentioned proces can't be done with a simple chemistry set. Perhaps you are so used to your well-equiped lab that anything less means it can't be done? Remember that the greatest chemists in history had less to work with than us and that didn't stop them to define the field. Don't rely on so much technology and spend some time on getting reactions done on the benchtable, I'd say.

    12. Re:Titan's active geology is very cool by Anonymous Coward · · Score: 0

      This is why you don't have any friends and never get invited anywhere.

    13. Re:Titan's active geology is very cool by Anonymous Coward · · Score: 0

      "partial hydrolysis under high vacuum?"

      Huh? How do you you get a gas and a liquid with a high vapor pressure under high vacuum? I mean, you can do it, but you wont have much reactant left.

    14. Re:Titan's active geology is very cool by Anonymous Coward · · Score: 2, Informative

      On Mars, it is expected that methane would be destroyed pretty quickly due to photochemistry, and in order for th current, low concentrations to maintain a steady state, there has to be a source somewhere. Titan would be a difference case, as it receives less sun light, may have started with a much larger source of methane. It wouldn't take as large of an ongoing source of methane to result in the levels we see on Titan, as opposed on Mars.

  2. ESKIMO PUSSY IS MIGHTY COLD. by Anonymous Coward · · Score: 0, Flamebait

    Is it colder than Eskimo pussy? Because I've heard that's also mighty cold.

    1. Re:ESKIMO PUSSY IS MIGHTY COLD. by Anonymous Coward · · Score: 0

      Says the person with no sense of humor

  3. Too bad this isn't on Europa by Anonymous Coward · · Score: 0

    Too bad this isn't on Europa, or I would be able to make a 2001/2010 reference...

    1. Re:Too bad this isn't on Europa by Rosco+P.+Coltrane · · Score: 2

      Too bad this isn't on Europa, *and* there isn't a single black monoliths in sight, *and* Jupiter (well, Saturn, Jupiter is nowhere in sight either) isn't collapsing in on itself and isn't turning into a second sun, *and* there isn't a human crewed spacecraft there, *and* we're not receiving an ominous warning not to land there, *and* neither a psychotic computer nor Roy Scheider are involved, or you would be able to make a 2001/2010 reference.

      --
      "A door is what a dog is perpetually on the wrong side of" - Ogden Nash
    2. Re:Too bad this isn't on Europa by maxwell+demon · · Score: 1

      *and* there isn't a single black monoliths in sight

      Have you read what they say about Titan's atmosphere? Of course you cannot see the monolith.

      --
      The Tao of math: The numbers you can count are not the real numbers.
    3. Re:Too bad this isn't on Europa by andrewbaldwin · · Score: 2

      But you could make a Kurt Vonnegut one :-)

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

      Well worth a read by the way

    4. Re:Too bad this isn't on Europa by FatLittleMonkey · · Score: 1

      "Reference" doesn't mean he has to tell the whole fucking story.

      --
      Science is all about firing a drunk pig out of a cannon just to see what happens.
  4. Wild theory by maxwell+demon · · Score: 2

    Maybe the source of the methane is some exotic life form: They feed on the more complex hydrocarbons and reduce them to methane (I'm no chemist, so I don't really know whether this would be a possible way to gain energy). They cannot consume the methane to gain more energy because they are lacking oxygen, therefore the methane is the end product, just like CO2 for earth's life. The methane then goes into the atmosphere where it gets combined into more complex hydrocarbons using solar energy (that process is actually described in the article).

    --
    The Tao of math: The numbers you can count are not the real numbers.
    1. Re:Wild theory by MichaelSmith · · Score: 4, Insightful

      Yeah its interesting but it should be possible to calculate the amount of biomass required to do that. There is a hell of a lot of methane in this cycle on Titan which implies a lot of life. My guess is that the stuff would have to blanket the planet and it would need a fast metabolism. For me that means it must be in a subsurface ocean. The surface is too cold for a high energy metabolism.

    2. Re:Wild theory by Sigg3.net · · Score: 1

      They must be eating a lot of cheese.

        I get that too:)

    3. Re:Wild theory by Anonymous Coward · · Score: 0

      Such a calculation wouldn't be possible until Titan is well mapped and the geology is much better understood to exclude geological sources of methane, especially large ones like eruptions of underground reservoirs.

    4. Re:Wild theory by RockDoctor · · Score: 1

      it should be possible to calculate the amount of biomass required to do that. There is a hell of a lot of methane in this cycle on Titan which implies a lot of life.

      IF and only IF the source of the methane is biological. Which is not necessarily the case.

      The OP is implying a carbon cycle where, in effect, the sunlight alters (increases) the amount of net bond energy per carbon atom, by converting methane vapour into "higher" hydrocarbons ; then at the surface the metabolism of the (putative) organisms reverses the process to release methane and use the energy.

      Since the atmosphere of Titan is not opaque, I'd expect that in a living, evolving system ("living" and "evolving" are pretty much synonymous, to our present state of knowledge), an organism would appear rapidly which would directly use the solar radiation on the surface and out-compete the organisms which rely on the methane itself. I think such a simple cycle would be unstable. Remember that the only example we've got went through a drastic re-organisation of it's atmospheric chemistry (the "Great Oxidation Event") over half the lifetime of the solar system ago.

      The atmosphere of Titan is not extraordinarily out of thermodynamic equilibrium (as Earth's is, with methane and oxygen simultaneously present). So there are no grounds to anticipate the presence of significant life. Sorry ; I'd like it to be the case, but the atmospheric chemistry doesn't support the proposition. "Extraordinary claims require extraordinary evidence," as the saying goes. (OK : strictly that doesn't exclude the possibility of a biota that doesn't interact significantly with the atmosphere. That doesn't strike me as terribly credible.)

      --
      Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
  5. There could be gazillions of nano-cows on Titan ! by Taco+Cowboy · · Score: 1

    Cows produces methane on earth.

    But cows can't survive on Titan's climate.

    There must be a lot of "something" on Titan that are producing the massive amount of methane.

    They could be nano-cows.

    --
    Muchas Gracias, Señor Edward Snowden !
  6. Re:There could be gazillions of nano-cows on Titan by Runaway1956 · · Score: 2

    http://fc00.deviantart.net/fs71/f/2012/056/e/e/space_cows_by_jessicabane501-d4qxz3i.jpg

    You just can't trust those cows. I mean, cows have people trained in India to starve before they will consider eating a cow. Cows are smarter than we give them credit for.

    --
    "Windows is like the faint smell of piss in a subway: it's there, and there's nothing you can do about it." - Charlie Br
  7. Ultra-dense atmosphere at fault? by Hadlock · · Score: 4, Insightful

    Wouldn't Titan's ultra-dense atmosphere have something to do with this? Most meteors come in at a high angle of incidence, meaning they graze the atmosphere, then fall in as they're slowed down to a capture speed.
     
    Titan's atmosphere is something like what, three times as dense as Earth's atmosphere? It's up there with Venus, not Mars or Io, so shouldn't we be comparing it to planets, not moons? Keep in mind that visually, Titan is only about 8% smaller than Mars, and quite a bit larger than Earth's moon.

    --
    moox. for a new generation.
  8. The methane on Titan by Mister+Liberty · · Score: 2

    stays mainly in the crater.

  9. Re:There could be gazillions of nano-cows on Titan by Anonymous Coward · · Score: 3, Informative

    Actually the Bhagavad Gita allows an exception to killing in the face of starvation. A human being can sustain themselves without killing. Because life is sacred (crazy thought), an enlightened person should choose not to kill over killing. Because cows make milk and many dishes can be made from milk without killing, and mother's produce milk, cows are considered sacred. However, if you are faced with starvation, self-preservation is allowed. As religion goes, it's not quite as crazy as a god that depends on us killing Him so He can forgive us for our sins and save us from Himself.

  10. I know by p0p0 · · Score: 1

    It must be all the frozen Ewoks: http://youtu.be/5r_TlPwZOvU

  11. Life on Earth? by Anonymous Coward · · Score: 0

    rain that falls from Titan's skies is not water, but contains liquid methane and ethane, compounds that are gases at Earth's temperatures.

    [Pqqq'lwwzr] and that, children, is why it is impossible for life as we know it to exist on Earth.

    ... The source of Titan's methane remains a mystery

    [Pqqq'lwwzr] pffffffrrrrrrrrrrrrt Oh excuse me!

  12. Sort of like ... by PPH · · Score: 2

    ... Beijing.

    --
    Have gnu, will travel.
  13. Re:There could be gazillions of nano-cows on Titan by lennier · · Score: 1

    Cows produces methane on earth.

    But cows can't survive on Titan's climate.

    There must be a lot of "something" on Titan that are producing the massive amount of methane.

    Spherical cows, obviously.

    --
    You are not a brain: http://books.google.com/books?id=2oV61CeDx-YC