what is a planetarium

A planetarium is a theater built primarily for presenting educational and entertaining shows about astronomy and the night sky, or for training in celestial navigation. It is a place where you can go to see what the night sky looks like, with a large room that has a dome-shaped ceiling and many seats. A special projector in this room can shine images on the domed ceiling and show you the stars and other objects in the night sky. Many planetariums also have telescopes which you can look through and exhibits about space. The dominant feature of most planetariums is a large dome-shaped ceiling, which serves as a projection screen onto which scenes of stars, planets, and other celestial objects are made to appear. The projection can be created in various ways, such as a star ball, slide projector, video, fulldome projector systems, and lasers. Planetariums can also show the rising and setting of the stars and the motion of the moon and planets along the ecliptic, and can depict phenomena such as eclipses, auroras, or meteors.