Man did not see the opposite side until the spaceship landed there and photographed it. Astronomers had always thought that the backside should be similar to the front with many meteorite craters and lava seas. But the photographs showed a much different scene. The backside of the moon is very bumpy. Most are small craters and mountain ranges with very few lava seas.
Scientists are unable to explain the differences.
In theory, the probability of being hit by meteorites should be the same for both sides of the moon if it was a naturally formed planet. The explanation from the scientists is that the moon rotates around its own axis with a velocity of 16.56 km per hour, and it also revolves around the earth at exactly the same speed. Thus the same side always faces the earth. This phenomenon does not exist for any other planet and its satellites in our solar system-only for our earth and moon. For the last 300 hundred years, astronomers have observed many unexplainable phenomena about the moon.