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Spin of the moon

  1. Nov 9, 2005 #1
    i have been thinking about how the moon always faces earth from the same side. this means that the moon spins once per rotaion but how perfect is this does the side of the moon that we see slowley change over time or in 2000 years will we be looking at the other side. the spin of the earth is slowing down and i wonder if the moon is slowing it spin as well and by how much
  2. jcsd
  3. Nov 9, 2005 #2


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    It's tidally locked to the Earth. In 2000 years, we'll be staring at the same side too. As the Earth's rotation slows, the Moon's response is to climb into a higher orbit.

    Since the Moon's orbit is elliptical and not circular, its rotation can not keep perfect pace with its orbit. This causes it to appear to wobble a little bit, so we can actually see about 60% of its surface from Earth.
  4. Nov 9, 2005 #3
    why is it locked to the earth or how is it locked to the earth is a better question im sure asking why could open a hole other can of beans
  5. Nov 9, 2005 #4


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    Tidally locked means that the gravitational field varies by position: it is lopsided!
  6. Nov 10, 2005 #5
    ok what would cause this lopsidedniss and is this comon for moons on other planets?
  7. Nov 10, 2005 #6


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