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NASA Space Science

Titan May Have Water Ocean Under the Surface 64

RedEaredSlider writes "NASA's Cassini probe, in orbit around Saturn, may have discovered evidence for a liquid water ocean under the surface of Titan, Saturn's largest moon. The data comes from radar observations of the surface that measure Titan's rotation and tell how it is oriented relative to the plane of its orbit — its axial tilt. According to a paper to be published in an upcoming issue of Astronomy and Astrophysics (preprint PDF at arXiv.org), the new data showed that many of the planet's surface features were in the wrong place, sometimes off by as much as 30 kilometers (19 miles). Titan always presents the same face toward Saturn, just like the Moon does to Earth. But in those situations, one expects that the moon will be in the 'Cassini state,' which means that the axial tilt will have a certain value. In Titan's case, the axial tilt was measured at 0.3 degrees. That seemed too high if one assumed Titan was a solid body."
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Titan May Have Water Ocean Under the Surface

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  • I'd like to get a ticket for a swim. Even if it is one-way, it should provide good stuff for a blog to fill. I might even have (new) friends on facebook who I can invite for a fishing trip.

  • by assertation ( 1255714 ) on Saturday May 07, 2011 @02:42PM (#36057770)

    Sort of reminds me of lyrics from the Talking Heads song "Once In A Life Time"

    " under the rocks and stones there is water"

    http://www.youtube.com/watch?v=I1wg1DNHbNU [youtube.com]

  • Haven't they been saying this for a while now??? I remember seeing something like this a while back
  • I think we have a higher chance of finding water on Europa than on titan.
    • Re:Like Europa? (Score:4, Interesting)

      by Maritz ( 1829006 ) on Saturday May 07, 2011 @05:23PM (#36058626)

      The existence of liquid water on Europa is already pretty much a done deal due to the surface features that have been photographed. Richard Greenberg's "Unmasking Europa" is a particularly interesting read on the subject in my opinion as he outlines a strong case that the ice is much thinner than some planetary scientists believe. There are regions on the surface known as 'chaos' that appear to be formed by melt through from beneath the surface. Interestingly the celestial mechanics pointed to very high tidal forces on the Galilean moons just before the first Voyager probe arrived there and almost immediately found the incredibly actively volcanic Io.

      If there is water beneath Titan's surface I would imagine that it represents a much more difficult target for a drill/melt through probe than Europa, because of the thick atmosphere and the unknown rigidity of the surface, as well as the dangers of landing in liquid. Having said that, it's great to have more potential habitats in the solar system. Enceladus's ice plumes indicate possible pockets of water below the icy crust there too.

      The Europa-Jupiter System mission is scheduled for 2020 and should give a much richer pool of data on Europa, the Galileo probe sadly malfunctioned and was only able to provide a tiny fraction of the data that was intended, so there are relatively few high resolution photos available of Europa. The entire Europa catalogue can fit on one CD. The EJSM mission should also be able to settle the issue of just how thick the ice on Europa is. In his book Greenberg argues that the entire surface is recycled on the order of every few hundred thousand years at most, meaning that material from the surface could be cycled down to the ocean below, which would boost the chances of some kind of life existing considerably.

      One thing we can be pretty sure of is that if life is detected on Europa, we have to conclude that life is very likely indeed to be commonplace in the Universe.

    • by Anonymous Coward

      Yes, but we can attempt no landing there

      • Yes, but we can attempt no landing there

        No, that's only after Jupiter ignites and becomes a star.

        Besides, by the look of things all of that is obviously not going to happen for a good while yet. We're an extremely long way from achieving anything that's supposed to have happened according to those books.

  • Having an ocean under the ice doesn't mean water, it might be methane something or other instead.
    • Agreed. Looking at the paper [arxiv.org] they noticed the moon's axial tilt doesn't match current theories. So they assumed the moon had a water ocean, calculated what the characteristics of that water ocean would need to be to explain the discrepancy and said, "see, it's possible".
      • So they assumed the moon had a water ocean

        Nope. Previous research concluded Titan's body consists of about half rock and half water ice. They are saying some of that water ice is actually liquid. They aren't assuming anything, but rather just building on prior research like normal.

        • Directly from the abstract [arxiv.org]:

          We propose a new Cassini state model for Titan in which we assume the presence of a liquid water ocean beneath an ice shell

  • I seem to remember reading some very old sci-fi stories by the late Arthur Clarke that had this possibility as a theme.

    • by spauldo ( 118058 )

      Back then, all we knew about Titan was its size, orbit, and the existence of an atmosphere.

      It was exciting mostly because moons generally don't have atmospheres. It was an anomaly. Sir Arthur was one of the more science-oriented authors out there, but he didn't have much to work on, so he made stuff up. It was just a lucky guess.

    • by Trogre ( 513942 )

      Well, that and the same story was posted here over two weeks ago.

  • It doesn't matter, apart from an interesting scientific study. Once they are able to get people to the moon or mars profitably, then we can start worrying about water.
  • by Brad1138 ( 590148 ) <brad1138@yahoo.com> on Saturday May 07, 2011 @04:24PM (#36058346)
    I hope I live long enough to see them get a probe through the ice into the water of either Europa or Titan. It would be SO cool to see some form of alien life living there. At 44, I figure they better get moving, I got about 40 years...
  • by frovingslosh ( 582462 ) on Saturday May 07, 2011 @05:17PM (#36058600)

    new data showed that many of the planet's surface features were in the wrong place, sometimes off by as much as 30 kilometers (19 miles).

    I find it hard to take seriously any "scientific" paper which refers to Titan as a planet rather than a moon.

    • new data showed that many of the planet's surface features were in the wrong place, sometimes off by as much as 30 kilometers (19 miles).

      I find it hard to take seriously any "scientific" paper which refers to Titan as a planet rather than a moon.

      That's no Moon! It's a -- oh, wait... yeah, it is, my bad.

    • by rhook ( 943951 )

      It is actually considered to be a "planet-like moon", due to it having a dense atmosphere. It is also large enough to be a planet, being larger than Mercury (although having less mass).

    • The paper, of course, says no such thing. ibtimes.com, however, is quite silly.

  • So, when will the Lazarus and Klamp-G families start colonizing the place? I want my Tiger Moth!

  • Then it stands to reason that frozen samples of it may be freely orbiting in the Jupiter system having been smashed into orbit by impacts on Europa's surface. It'd be interesting to know if any mission planners are considering this when thinking about future missions like EJSM. Russia is thinking of sending a lander with the EJSM so maybe samples could be found on the surface. I guess a sample/return mission is well out of feasibility for the foreseeable future sadly. I personally think Europa is potentiall
  • by Anonymous Coward

    They better welcome there new human overlords.

  • As I recall, Titan also has amino acids.

    Shit just got real, yo.

  • by Lotana ( 842533 ) on Saturday May 07, 2011 @09:53PM (#36059712)

    The hypothesis that Titan may have liquids present has been around for a long time. And it used the orbit shape since its basis from the very beginning. That is why Huygens [wikipedia.org] atmospheric probe was designed to float just in case.

    However Huygens landed on a solid surface even though it was aimed at an area that had an appearance of a liquid. As far as I know the probe did not detect any evidence of liquids near the landing site nor from the aerial imagery. As such, I was under the impression that this hypothesis was disproved.

    If there were underground bodies of water present, surely Huygens would of picked up evidence of this in the atmosphere. Just seems like rather than working on other explanations for the orbit scientists still cling to the same assumptions with a little more justification.

    • Of every comment in this thread, this is the one I keep coming back to in hopes of seeing a reply.

      • by Anonymous Coward

        Well here's a reply..


        Preliminary findings seemed to confirm the presence of large bodies of liquid on the surface of Titan. The photos showed what appear to be large drainage channels crossing the lighter coloured mainland into a dark sea. Some of the photos even seem to suggest islands and mist shrouded coastline.

  • I thought the Earth's moon always presented the same face toward the sun. Am I totally misunderstanding what this means?

    • you thought wrong. The moon isn't tidally locked with the sun... it's locked with the EARTH.
      • by sking ( 42926 )

        I understand that the moon is tidally locked with the earth. What I don't understand is why the moon's movement is described as being "such that the same face is always facing the Earth." It appears to me as though the same area of the moon is being constantly lit by the sun. Doesn't that mean that that "face" is always facing the sun? I am not trying to be argumentative nor refute Cassini's Laws. I am just trying to understand the meaning of "face" in this particular context.

        • There is no dark side of the Moon. The Moon is tidally locked to its planet like most moons, meaning its orbit is the same length of its revolution which is about 27 days. This means a day on the Moon, sun rise to sun rise is about 27 days. The phases on the Moon that we see are a result of that day.
        • Face is what we see. The portion of the moon that is being lit by the sun is constantly changing, but we only have the pleasure of seeing the same portion of the moon, no matter what. When the sun is lighting up that portion - full moon. When the sun is lighting up the opposite portion - new/no moon. Everything else is in between.

          • by sking ( 42926 )

            I totally get it now. Thanks, folks.

            Now to get over feeling like a total ignoramus.

  • so yes they do have water there. However they hate taking baths, which indicates the water could be of poor quality.
  • Whats he chance of having life here or on Europa?

Were there fewer fools, knaves would starve. - Anonymous