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Planets orbit

  1. Aug 11, 2010 #1

    What makes the planets to keep their position on the orbit (the same orbit). Shouldn't be attracted by the gravitation of the star ?

  2. jcsd
  3. Aug 11, 2010 #2
    Hi there,

    To be very simple, their speed!!!
  4. Aug 11, 2010 #3
    they keep in their orbits due to the force of attraction or gravitational pull which depends on the distance of the planets and the radius of the orbits from each other and the sun.
  5. Aug 11, 2010 #4
    And what give them the speed (motion)?
  6. Aug 11, 2010 #5


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    The angular momentum of the original spinning cloud of gas/dust that formed the solar system.
  7. Aug 11, 2010 #6
    And why it doesn't stop ?
  8. Aug 11, 2010 #7


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    Newton's laws of motion.
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