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Pictures of Titan's Lakes

Posted by samzenpus on from the in-space-nobody-can-hear-you-fish dept.

sighted writes "For decades, scientists have wondered if the thick orange haze that shrouds Saturn's giant moon Titan hid lakes of liquid methane on the surface, but there was no way to confirm it, until now. The Cassini flyby of July 22, 2006 took these striking images and were released today."

6 of 119 comments (clear)

  1. More information at ... by Anonymous Coward · · Score: 5, Informative

    This other location at the Cassini site, and this older article from the BBC.

    The original article is in the journal Nature, but you need a subscription to view it. You can still read the abstract, though.

  2. Re:It reminds me... by necro2607 · · Score: 2, Informative

    I would imagine the imagine is a long strip like that because the Cassini radar instrument simply flew along in a straight line, therefore only capturing a narrow strip of surveyed data along that straight line (as opposed to getting a large square or circular capture).

  3. We've already landed there ffs. by mollymoo · · Score: 4, Informative

    Am I the only one who can remember that we put a lander on Titan a good 18 months prior to taking this image? The presence of liquid methane on the surface was confirmed one week later. Nice image, bad caption.

    --
    Chernobyl 'not a wildlife haven' - BBC News
    1. Re:We've already landed there ffs. by Tablizer · · Score: 4, Informative

      The lander did *not* detect existing pooled or flowing liquid. The radar evidence appears to be the first evidence of existing pooled/flowing liquid. The lander found plenty of *hints* of erosion typical of that associated with liquid, but it did not detect any active liquid (except maybe methane mist). The area it landed at is often characterized as a "dry lake bed".

      --
      Table-ized A.I.
  4. Re:Confirmed? by Nasarius · · Score: 3, Informative
    They seem fairly certain. From the original Nature article:
    Only two hypotheses are consistent with the radiometric and morphological characteristics of the dark patches: either we are observing liquid-filled lakes on Titan today, or depressions and channels formed in the past have now been infilled by a very low-density deposit that is darker than any observed elsewhere on Titan. The absence of any aeolian features in this area makes low-density, porous, unconsolidated sediments unlikely. This, combined with the morphologic characteristics of the dark patches, leads us to conclude that the dark patches are lakes containing liquid hydrocarbons.
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    LOAD "SIG",8,1
  5. Re:Liquid methane? Maybe. by stoicio · · Score: 4, Informative

    "The images are blatantly false-colour. The blue areas meant to potray liquid (making people think of water) but could just as easily be ice or lava flows."

    Actually the intensity of the backscatter data is what is being shown.
    The brightness is logarithmic, therefore anything dark is very smooth
    and anything really bright is very bumpy. Since it is a log scale and
    there is a good idea what kind of backscatter to absorption ratio to expect
    from the synthetic aperture radar for various targets, they can conclude that
    the dark patches are glassy/ice-rink flat.

    They can also conclude that the dark patches could be liquid based on
    change detection, provided they have another series of overlapping data
    to compare. If the glassy areas undulate slightly between images (waves)
    they are probably liquid.

    Having noted this, 500 metres is kind of crappy resolution for
    SAR data. You'd think they'd make a closer flyby or put a better
    instrument onboard. I believe 1 (one) metre resolution SAR was available
    from instruments at the same altitude when cassini was designed.
    NASA just cheaped out.