Man in the Moon then cooled, becoming smooth, basalt rock. The near side of the Moon, containing these maria that make up the man, is always facing Earth. This is due to a tidal locking or synchronous orbit. Thought to have occurred because of the gravitational forces partially caused by the Moon's oblong shape, its rotation has slowed to the point where it rotates exactly once on each trip around the Earth. This causes the near side of the Moon to always turn its face toward Earth. Man in the Moon The Man in the Moon refers to any of several pareidolic images of
Gravitation of the Moon spacecraft acceleration can be measured by small shifts in frequency of the radio signal, and the measurement of the distance from the spacecraft to a station on Earth. Since the gravitational field of the Moon affects the orbit of a spacecraft, one can use these tracking data to detect gravity anomalies. However, because of the Moon's synchronous rotation it is not possible to track spacecraft from Earth much beyond the limbs of the Moon, so until the recent GRAIL mission the far-side gravity field was not accurately known. A major feature of the Moon's gravitational field is the presence of