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What exactly is Pluto?

  1. May 20, 2005 #1
    What exactly is Pluto? It says "Pluto is the only known planet which cannot be placed in the terrestrial versus gas-giant planet classification -- it is small, but not very dense." What does that mean? We couldn't live on gas planets because theres no surface there right? But could we live on Pluto? How much do we know about Pluto?
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  3. May 20, 2005 #2
    Last edited: May 20, 2005
  4. May 20, 2005 #3


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    moved :smile:
  5. May 20, 2005 #4


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    What this means is that the terrestrial planets, are small and dense because they are mostly made form rock. The low density of Pluto suggests that it contains little or no rock and just might be composed of various ices. There is some argument that Pluto shouldn't even be considered a planet at all but is just the largest member of the Kuiper belt, which consists of like icey bodies.
  6. May 20, 2005 #5
    on wikipedia it says that it and Charon, it's sattalite, share the same atmosphere, and sometimes the atmosphere will freeze and it will form a single icy body
  7. May 21, 2005 #6
    It's very evident that Pluto is not akin to any other of the 8 other planets, so I prefer to call it a minor planet

    I also think that is probable that in the future some object bigger than Pluto will be found in the Kuiper Belt (Sedna and Quaoar have been close to the mark)
  8. May 21, 2005 #7
    Er..What? No, this isn't correct. I think you must have read it wrong
  9. May 21, 2005 #8


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    I gotta say, that's the weirdest thing I've ever heard.


    OK, it does say this:
    "It is thought by some that Pluto shares its atmosphere with its moon."
    but nothing about a single solid body. Maybe he was misunderstanding this:
    "Pluto and Charon are also unusual among planets in that they are tidally locked to each other."
    Last edited: May 21, 2005
  10. May 22, 2005 #9
    Well, the article also says (correctly) that the atmosphere freezes regularly.

    What it fails to clarify is that if Pluto and Charon do share an atmosphere, then it would only be shared when the atmosphere is not frozen.
  11. May 23, 2005 #10


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    an introduction...
    http://www.seds.org/billa/tnp/pluto.html [Broken]

    that was a typo right? :cry:

    Thanks for clarifying that Pete!
    When Pluto's atmosphere freezes, it falls to the ground as a kind of snow (not water-snow, of course).
    Last edited by a moderator: May 2, 2017
  12. May 23, 2005 #11
    I think that article pretty much sums up my feelings about Pluto. If it were only discovered today, I think we'd classify it as a large comet/asteroid (as Sedna probably will be), but since it's been officially labeled a planet for the last 75 years, why bother changing it now. It would just create too much confusion. Although, I have to admit it *would* be fun to watch the numerologists and astrologers squirm. :devil:
    Last edited by a moderator: May 2, 2017
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