The Moon

 

Lunar Phases

 

Lunation

The Astronomy Picture of the Day recently presented an image of the moon as it appears in the course of it's rotation around the earth. A few notes:

The complete cycle of the moon's orbit is called a lunation.

The moon doesn't orbit circularly but instead a little elliptically -- it's apparent size as viewed from the earth changes.

The moon wobbles as it orbits the earth.