Celestial bodies

彗星
Comet

An icy body that grows a tail near the Sun.

Most tails need the comet to be brighter than magnitude 4 to beat city light.

Related terms

Planet — A large body orbiting a star and not shining by itself.
Venus — The brightest planet, reaching about 47° elongation.
Jupiter — The largest planet, around −2.5 magnitude.
Saturn — The ringed planet; separating rings from disc needs about 30×.