Who can tell me in detail why the moon always faces the earth? thank you

The moon always faces the earth with a face, because the autobiography of the moon is the same as that of the revolutionary period. (27.32 166 days)

To understand this phenomenon, we can do an experiment. Draw a circle and mark the positive east, west, north and south directions. You stand at the center of the circle (representing the earth), find another friend, stand on the circle, let his face face forward (that is, don't twist his neck), move counterclockwise along the circle, and ask his face to always face the center of the circle, that is, you. Then such a process basically simulates the process of the moon going around the earth.

Obviously, in this process, your friends always face you. Let's understand why in such a process, period of revolution is equal to the rotation period.

Your friend starts from your due north, turns around you, and appears in due north again. He completes a revolution. It is similar to the time that the moon goes around the earth once. )

Let's see what his rotation time is. We might as well set your friend's posture when he is in your due north position and his face is facing due south as the initial posture ... Then we can find that when your friend moves counterclockwise to your due west position, his rotation posture rotates 90 degrees counterclockwise. If your friend doesn't "spin" in this process, then when he is in this position, he is not facing you, but still facing due south. However, in the actual experiment, your friend faces due east in this position, so he rotates 90 degrees counterclockwise around himself relative to the initial position.

Similarly, when he walked directly south of you, he autobiographed 180 degrees relative to the initial posture. When he was walking due east of you, he autobiographed 270 degrees relative to his original posture. When he walked to your true north again, he autobiographed 360 degrees relative to his original posture. In other words, he completed a rotation cycle.

Because completing a revolution only completes a rotation process, in time, this rotation period is equal to period of revolution. Because in the whole process, your friend always faces you with his body and face, that is to say, the moon always faces the earth.

I hope it helps you!