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Close-Up Images Show Ceres' Bright Spots In Great Detail

New submitter Actual_Alien writes: Since the Dawn probe arrived at Ceres, everybody has been wondering about the mysterious bright spots on an otherwise dark dwarf planet. New images sent back recently show the spots in better detail than ever — 140 meters per pixel. NASA used composite imagery to get high-quality exposures of both the bright areas and the surrounding dark areas. We can now clearly see a wide, flat crater with a rim that's almost vertical in spots. The brightest area is right at the center, with other markings to the upper right in the image. Dawn's orbit around Ceres also allows scientists to look at the crater from other perspectives, and they've generated a pair of animations to illustrate better what it looks like. One of them highlights the bright spots, while the other shows color-coded topography.

5 of 43 comments (clear)

  1. Re:Exposed ice? by Rei · · Score: 4, Insightful

    What I've read from following the story at the Planetary Society blog (and assuming I'm remembering correctly) is that the team does not find the spectra of the bright spots to be indicative of ice thusfar. They still don't know what they are but salts of some sort are a leading hypothesis.

    Very interesting terrain coming into view here - and not just how the bright areas seem to all be localized depressions. There's a lot of fine, very straight rift/fissure structures, like some sort of horst/graben terrain, tracing their way across the crater. Almost like Enceladus's tiger stripes or some of the rifting on Europa. We also see such terrain here in Iceland due to continental spreading. The features run parallel to each other locally but the directions are different in different parts of the crater, so whatever the cause of the pressure differential, it's nonuniform across the crater. Really fascinating to see!

    If I had to speculate wildly... I'd wager that it might be a sign of localized (and perhaps extinct) soda cryovolcanism like on Enceladus, with the water sublimated off and only the salts left behind. But that's just me talking out my arse ;)

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  2. Re:Exposed ice? by Rei · · Score: 3, Interesting

    Whoa... just noticed that the grabens seem to be younger than the (presumed) salts, even going straight across one of the super-bright areas. Seems to make it hard to envision that both were simultaneously caused by impacts (my default presumption). Seems to me that if this was caused by an impact, the active tectonic forces persisted for long after the impact (say, due to resultant localized internal heating), long enough for the salt flats to fully develop, lose their volatiles, and fully relax; or otherwise, that the forces that made them are unrelated to impacts altogether.

    Oh, I can't wait to hear what the experts come up with! :)

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  3. Re:SW in space by Rei · · Score: 3, Interesting

    Dawn is actually an averted disaster due to its failed reaction wheels. The mission team came up with a really clever plan to achieve all of the same science goals using even less fuel than had been planned by using the ion engine more, not rotating as much in Ceres orbit, etc. It's slower, but they saved the mission.

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    You don't exist. Go away.
  4. Re:Images... by wonkey_monkey · · Score: 3, Insightful

    Well just hang on to the image in your head and don't look at the [truth]

    say most religions.

    You're bound to get dissapointed...

    What's so disappointing? What were you hoping for? A crashed alien spaceship? Cthulhu?

    I'm not disappointed in the slightest. This is awesome science.

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    systemd is Roko's Basilisk.
  5. Re:Exposed ice? by TheDarkMaster · · Score: 4, Insightful

    My kingdom for a lander with a drill...

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    Religion: The greatest weapon of mass destruction of all time