How Long Is a Moon Day?

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According to NASA, one moon day is equal to 27 Earth days, which is the time the moon takes to complete its spin. The moon is tidally locked, so it always shows the same face to the Earth.

The moon orbits the Earth at a distance of about 239,000 miles. It is rocky and has a solid surface. The craters and pits on the moon are a result of impacts. According to NASA, the surface features that create the face known as the “man in the moon” are the result of impact basins on the moon with dark basalt rocks.

The orbit of the moon is slowly spiraling away from the Earth, a process that increases its distance at the rate of about 1.5 inches per year.