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Planet movement

  1. May 30, 2009 #1
    Just a quick question
    Are the planets totaly locked in there orbits forever or do they slowly get drawn in closer to the sun?either by the sun's gravitational pull or simply by the sun expanding?
    Thanks in advance for any replys
  2. jcsd
  3. May 30, 2009 #2


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    Given that the Sun is slowly losing mass as it burns it fuel, the planets will slowly move away from the Sun.
    In a few billion years the Sun will then expand into a red giant, engulfing the inner planets.
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