Here's why:
* Tidal forces: The Moon's gravity pulls on the Earth's oceans, causing tides. This pull also causes the Earth to slightly bulge towards the Moon. This bulge, in turn, exerts a gravitational pull on the Moon, accelerating it and causing it to move slightly farther away.
* Angular momentum: The Earth and Moon are constantly exchanging angular momentum, with the Moon gaining a tiny amount. This increase in momentum causes the Moon to move into a higher orbit, increasing the distance between the two.
However, this change is very slow. It would take millions of years for the distance to significantly increase.
In conclusion: The Earth-Moon distance is increasing very gradually, but it's not a dramatic change that we need to worry about.
