Scattered pieces of rock left over from the formation of the Moon and from the rest of the solar system collide with the moon and heavily crater the surface. Very large impacts form gigantic basins. The Moon slowly moves away from the Earth because of tidal forces.
Basaltic lava flows seep into the basins to form the low dark plains seen on the side of the Moon that faces the Earth. Tides from the Earth force the lava-filled basins to point to the Earth, as the Moon continues to move away.
Meteors continue to hit the moon, and crater the surface. Some large craters like Copernicus were formed as late as 0.9 Billion Years Ago. The Moon moves to its present location.