# Far Side of The Moon

The moon really does rotate at exactly the right speed to keep the same face toward the Earth at all times. It does it with enough precision that as long as man has looked up at the moon, he has always seen the same side.

This is too much precision to be considered coincidence, so there must be another force at work. And that force is gravity, the same gravitational attraction which gives the Earth its tides. As the moon orbits the Earth, its gravitational pull attempts to "stretch" the Earth. We see this effect on the water, causing a high tide on the side both facing the moon, and facing away from the moon as the Earth tries to morph into a eggish stretched sphere.

The Earth is doing the same to the moon, with some success. The moon actually is not a perfect sphere. Viewed from the poles it is very slightly elongated.

Try the following simple experiment: Take a rod, say 100 meters long and 10 meters wide and put it in orbit around a large celestial body such as the Earth and wait. See what happens? The rod orients itself like a spoke pointing toward the gravitational center. This is because the pull of the Earth is stronger at one end of the rod than the other.

The same effect is occuring with the moon, keeping one face oriented toward the Earth. The Earth doesn't experience the same effect with the moon because of its disproportionally larger mass.

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