Planetarium projector

A Zeiss Universarium Mark IX starball projector

A planetarium projector, also known as a star projector, is a device used to project images of celestial objects onto the dome in a planetarium.

Modern planetarium projectors were first designed and built by the Carl Zeiss Jena company in Germany between 1923 and 1925, and have since grown more complex. Smaller projectors include a set of fixed stars, Sun, Moon, and planets, and various nebulae. Larger machines also include comets and a far greater selection of stars. Additional projectors can be added to show twilight around the outside of the screen (complete with city or country scenes) as well as the Milky Way. Still others add coordinate lines and constellations, photographic slides, laser displays, and other images. The OMNIMAX movie system (now known as IMAX Dome) was originally designed to operate on planetarium screens.

Companies that make (or have made) planetarium projectors include Carl Zeiss Jena (Germany), Spitz (US), Goto and Minolta (Japan), Evans & Sutherland (US), Emerald planetariums (Israel) and Ohira Tech (Japan).