Does the Moon rotate? (Beginner)

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 be 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!

This page was last updated on July 18, 2015.

About the Author

Britt Scharringhausen

Britt studies the rings of Saturn. She got her PhD from Cornell in 2006 and is now a Professor at Beloit College in Wisconson.

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