The Moon Drifts About an Inch Farther From Earth Every Year

The distance between Earth and the Moon is not fixed. NASA states that the Moon is slowly moving away from Earth, getting about an inch farther away each year. An inch is a tiny step compared with the distance involved, so the change cannot be noticed by looking at the sky, and the Moon appears the same size from one year to the next. The same NASA page explains another feature of the pair. Earth and the Moon are tidally locked: the Moon rotates at the same rate that it revolves around Earth, which NASA calls synchronous rotation. As a result the same hemisphere of the Moon faces Earth all the time.