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The Question

(Submitted February 18, 1998)

The Earth's moon orbits the earth with one side always facing the Earth. Do other moons orbit their respective planets in the same manner?

The Answer

Most of the satellites in the solar system rotate synchronously like our moon (see An example of one that doesn't is Saturn's moon Hyperion. Its rotation is actually chaotic. You can find out more about it at

Also, (

, which is a table of orbital and rotation periods, among other things.

Damian Audley and John Cannizzo
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