A stellarium is a

three-dimensional In geometry, a three-dimensional space (3D space, 3-space or, rarely, tri-dimensional space) is a mathematical space in which three values (''coordinates'') are required to determine the position (geometry), position of a point (geometry), poi ...

map of the stars, typically centered on

Earth Earth is the third planet from the Sun and the only astronomical object known to Planetary habitability, harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all ...

. They are common fixtures at

planetarium A planetarium (: planetariums or planetaria) is a theatre built primarily for presenting educational and entertaining shows about astronomy and the night sky, or for training in celestial navigation. A dominant feature of most planetariums is ...

s, where they illustrate the local deep space. Older examples were normally built using small colored balls or lights on support rods (painted black to make them less obvious), but later examples used a variety of projection techniques instead.

References

External links

What is a stellarium?
Planetarium projection {{map-stub