Christopher Gluck.. age 8 of Rochester.NY

Why doesn’t gravity pull the moon down?

We are told that the force of gravity holds us on the face of the earth. It pulls down a falling stone and the raindrops. Birds fight against gravity to stay in the air. So do airplanes. Birds and planes can defeat the pull of gravity for a little while. Our big round moon knows how to fight against the pull of earths gravity all the time.

Fix a ball on the end of a string and swing it round and round your head. You can feel the ball pulling to break away from the string. Put some water in a pail and swing it around. The water will not spill. out while the pail is spinning. It will star pressed in the bottom of the pail. You are playing with centrifugal force. This powerful force operates on things spinning around. It gives them power to pull away from the center.

Now the moon is always spinning around the earth. This gives it centrifugal force to pull away from the earth. The earth’s gravity is always pulling at the moon but it cannot pull it all the way down because the moon pulls back with centrifugal force. The two forces balance out to keep our moon just where it is in the sky.. so far and no farther.

For more information on the moon go to:http://www.MoonPhases.info/#Moon_Information