Does the Moon rotate?
Does the Moon rotate as it goes around the Earth? I thought it didn't because it always keeps one face toward Earth!
The Moon definitely has to rotate to keep one face toward the Earth. If the Moon didn't rotate, we could see all parts of it as it revolved through its orbit.
Get a volunteer to the the Earth for you, and you pretend to be the Moon. Walk in a circle around the Earth, and always keep facing the Earth. Now, what do you see in the background? You'll see different parts of the room as you go around. This proves that you are rotating.
Now, try walking around the Earth without rotating; that is, always face one wall of your room as you move in a circle. Now, does the Earth only see one face of you? Or can they see all sides of you?
You can trade places, and play the Earth while the other person is the Moon, and see what happens!
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- Why does the Earth only see one side of the Moon?
- Does the Moon rotate? Are there other moons that always keep one face toward their planet?
- The Moon slows the Earth's rotation, but how fast was it spinning billions of years ago?
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