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Name: Doreen
Status: other
Grade: other
Location: NV
Country: N/A
Date: N/A


Question:
Is distance between earth and Moon increasing? Why?


Replies:
Yes, about 3 meters per century. The Earth has been slowly moving away. As a result the Earth's rotation is slowing down very slowly as well.

David Levy


Yes, the Earth-Moon distance is increasing. We know this because the Apollo Astronauts placed reflective mirrors on the moon from which we can bounce of lasers from the Earth and measure the time it takes for the light to travel back and forth between the Earth and the Moon. Successive measurements show that the Earth-Moon distance is indeed increasing.

This is counter to the idea that the gravitational forces between the Earth and the Moon should bring the two bodies together and is taken to mean that there are other forces at work here. One of the suggestions is that the Moon was a product of a collision between the proto-Earth and another celestial object which produced the current Earth and the Moon. This hypothesis then suggests that in the early history of the Earth and the Moon, the two bodies were very much closer to each other and the collision forces that created the two bodies is what is forcing them farther apart from each other.

Greg (Roberto Gregorius)



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