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Alternating planetary phase layers

  1. Mar 21, 2005 #1
    Terrestrial planets in general are solid, or solid with a liquid core. Gaseous planets in general are liquid, or liquid with a solid core.

    Can there be planetoids with substantial alternating layers of solid - liquid - solid, or liquid - solid - liquid? (I do not consider Earth's hydrosphere as substantial in this regard.) I believe there are some known moons which qualify.
  2. jcsd
  3. Mar 22, 2005 #2


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    As I understand it, the Earth has a gaseous atmosphere, over much of its expanse, a liquid ocean, a solid crust, liquid rock pockets, a solid layer, a liquid layer, and a solid metal core.

    http://volcano.und.nodak.edu/vwdocs/kids/volcano_project/volcanoes.html [Broken]

    I see no reason why this couldn't happen elsewhere.
    Last edited by a moderator: May 1, 2017
  4. Mar 23, 2005 #3


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    Europa (certainly), Ganymede (almost certainly), and Callisto (maybe) are all at least solid-liquid-solid.

    The state which matter is in depends (at least) on its composition (mix of compounds), temperature, and pressure; with a huge set of inputs of the physical properties (e.g. phase diagrams) of a great many compounds, the appropriate geophysical equations (for determining equilibrium conditions), and a lot of patience you could have a lot of fun making all kinds of strange planets! Oh, and making sure you get all the chemistry right too will earn you extra gold stars!
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