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Planet Formation Question

  1. Nov 17, 2009 #1
    Is it common for rocky planets to form closer to a star and gas planets further?

    Why or why not is this?
  2. jcsd
  3. Nov 17, 2009 #2
    Well I don't know how many terrestrial planets have been found around other stars... as far as I know there haven't been any. Reason being is that they are too close to the star and fairly small to be directly observed.

    The reason they form closer to the star is simply because they are made out of heavier materials
  4. Nov 17, 2009 #3
    Before the discovery of "Hot Jupiters", "Hot Neptunes" and "Super-Earths" people expected the rocky planets to form inside the "Ice Line" and gaseous/icy planets to form outside of it. The "Ice Line" is the distance around the proto-star at which ice can condense from gaseous into solid form, and it means a lot more material - commonly called "ices" - becomes trapped by the proto-planets and thus they form heavier than the rocky planets.

    Since then we've learnt that kinds of planets can form in one place then migrate inwards or outwards from the proto-star. Many of the known exoplanets seem to have migrated from beyond the Ice Line.
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