Moon

The term moon is a geographical category. Moons exist in the Great Dark Beyond, which is apparently the term for what we would call "outer space".

Moons visible from Azeroth


Azeroth had two moons:
 * The larger, bright and silver moon is known as the White Lady. The night elves know and worship it as Elune while the tauren refer to it as Mu'sha (the left eye of the Earthmother) in Sorrow of the Earthmother.
 * The smaller, cool blue-green moon, was known as the Blue Child. The Earthmother sent it to explore and study the rest of the universe shortly before the release of The Burning Crusade. This removal was possibly due to a graphical error. The Blue Child has yet to return.
 * When the two moons are in perfect alignment, it is an extraordinary celestial event called the Embrace.
 * Just before Loken in Halls of Lightning there is a globe/projection of Azeroth with its two moons in orbit around it.

Moons visible from Draenor
Draenor had one moon:
 * Draenor's moon is known as the Pale Lady.

Moons visible from Outland
Outland has an indeterminate number of moons:
 * It still has the Pale Lady.
 * Other spheres now existed as well, including a rosy one, and a smaller light blue one. These may be other planets, seen through "windows".

Video
Short video of the original two moons as seen in an earlier version of the game. buz43232cdE

Trivia

 * In the Warhammer universe, there are also two moons: Mannsleib, which is like Earth's moon, and Morrslieb, a green (however not blue-green), smaller and magical moon.
 * Multiple moons are a common element of many fantasy and science fiction settings.