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How the planets get their spherical shape

  1. Jun 13, 2013 #1
    how the planets get in spherical shape if the they are formed by a big explosion ?
     
  2. jcsd
  3. Jun 13, 2013 #2

    chroot

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    Spheres of matter are the most stable shapes when pitted against the relentless force of gravity.

    - Warren
     
  4. Jun 13, 2013 #3

    davenn

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    and they werent formed by a big explosion :)

    google accretion disk and solar system formation

    cheers
    Dave
     
  5. Aug 24, 2013 #4
    Planets get a spherical shape from gravity. Once a protoplanet (Baby Planet) reaches a certain radius, gravity crushes it into a spherical shape.
     
  6. Feb 23, 2014 #5
    The key concept you're looking for is hydrostatic equilibrium. If a celestial body is massive enough, its gravity will cause it to assume the optimal shape which balances gravity and pressure. This is a spheroid.
     
  7. Feb 23, 2014 #6

    SteamKing

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  8. Feb 24, 2014 #7
    If I remember correctly, there was an experiment with particles in the space station (wasn't it salt?) and the particles formed together in a spheroid shape.

    It is natural.
     
  9. Feb 24, 2014 #8

    ChrisVer

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    I thought that planets needed an explosion (shockwave) to be formed out of nebulae... for example an explosion would allow a condensate (not like the boson ones) to be formed -as an origin of initial gravitational attraction- and thus the whole gas around would start "falling" into that and form the planet.
    Due to the geometry of a sphere, it's the most favorable (energetically) shape to be formed... of course it's not a perfect sphere (for example the spin makes it more like an oval).
     
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