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The moon moves in a near-circular orbit around earth

  1. Aug 25, 2006 #1
    examine the truth of the statement

    "the moon moves in a near-circular orbit around earth. because the earth is so much more massive, it own motion is not appreciably affected by the moons presence"

    plz help
  2. jcsd
  3. Aug 25, 2006 #2


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    this does not belong in "cosmology", but rather in "general astronomy"

    the mass of the moon is about 1/81 times the mass of the earth

    In the course of a month, the earth and moon revolve around a common center of mass
    which is close to the center of the earth---within about 3000 miles I reckon.
    so the earth's motion is hardly noticeable

    so in its trip around the sun, the earth WOBBLES a little because of it and the moon doing this monthly circling around each other.
    but that wobble is very slight

    like you whirling something on a string----something that only has a mass of 2 pounds, or 1/80 of your mass. You are going to wobble a little as you whirl it---but you hardly notice that, most of the moving is done by the less massive thing.

    please put questions like that in General Astronomy
    or if it is a homework school problem then it should be in "Homework Help" section
    Last edited: Aug 25, 2006
  4. Aug 25, 2006 #3
    thanks 4 da help
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