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Other side of Moon

  1. Mar 18, 2005 #1
    It's a simple basic question.But I don't know the answer exactly. Why we can't see the other side of moon?
  2. jcsd
  3. Mar 18, 2005 #2


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  4. Mar 18, 2005 #3
    You only see one side of the moon because the moon and the earth have a quasi 1-1-spin-orbit-coupling. This means that if the moon has rotated 360 degrees around it's axis, it also has completed one full orbit around the earth. Thus you only see one side of the moon, seen from one fixed position on the earth.

    However since the orbit is not circular but elliptical you get two effects called libration in longitude and libration in latitude. They result in a kind of east-west rocking and a north-south-nodding up and down. Due to these effects, we actually see about 55% of the moon's surface...a little bit more then half the moon surface

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