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I How can rotation with same phase be possible?

  1. Mar 15, 2017 #1
    How can we calculate the rotation without seeing change of phase of object like in case of moon,we see the same phase of moon but how it can be rotating.
    So rotation without change of phase is possible if yes or no than how and why ?.
     
  2. jcsd
  3. Mar 15, 2017 #2

    phinds

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    The moon rotates around the Earth. If it did not rotate on its axis, how could it keep the same face towards the Earth?
     
  4. Mar 15, 2017 #3
    So rotation depends on what face you are seeing?
    Or moon's rotation is different kind of rotation?
     
  5. Mar 16, 2017 #4

    CWatters

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    The phase of the moon depends on the angle Sun-Moon-Earth....

    moon angle.jpg

    This changes with a cycle lasting about 28 days because that's how long the moon takes to orbit the earth.

    The phase of the moon does not depend on the rotation of the moon about it's own axis. The light and dark areas are not painted onto the surface of the moon :-)
     
  6. Mar 16, 2017 #5

    davenn

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    why are we discussing this again ?

    in your other thread in the astronomy section
    https://www.physicsforums.com/threads/spin-or-rotation-of-moon.907744/

    this was all answered for you


    Dave
     
  7. Mar 16, 2017 #6

    russ_watters

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    Please do not create duplicate threads. If there is anything you still don't understand, just ask in the thread you already have. Thread locked.
     
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