[anobjectivist]

The moon and earth orbit each other around a center of mass that is slightly below the earth's surface to my knowledge. The moon is a separate entity than the earth, but technically orbits the earth. I don't know what you're getting at.

[RightWhale]

There are two other moons of earth. One is Cruithne, and there is the asteroid discovered last year, I don't know if it has an informal name. The other two are also resonantly locked with earth, but their apparent orbits as seen from the earth's perspective are far from elliptical at this time--horseshoe-shaped. Nevertheless the moon, Luna, is gradually changing its orbit from elliptical to horseshoe. Whether it eventually becomes a true Trojan point orbit is unlikely since other planets, mainly Jupiter, exert a strong influence. The moon has escaped, but it is taking its own sweet time leaving the 'hood.

[HighWheeler]

Luna is constantly leaching energy from each rotation around the Earth, and is adding distance from us every day. There will be day in the far, far future that Luna finally escapes the Earth's gravity and ventures off on its own. It will be a tiny light by the time that happens.

BTW, do you know that the Earth has a second moon? It's called Cruithne, and it has an incredible complex orbit.