Celestial bodies

月球
The Moon

Earth's only natural satellite, 3474 km across.

It drifts about 3.8 cm farther away every year.

Related terms

Mars — The red planet, about −2.9 magnitude at opposition.
Mercury — The innermost planet, never more than 28° from the Sun.
Comet — An icy body that grows a tail near the Sun.
Asteroid — Small rocky bodies, mostly between Mars and Jupiter.