Munich was the world's first city to have a projection planetarium – the legendary Carl Zeiss Model I.
The first idea of such a machine that would show the starry sky as star gazers would experience it out in the open came from Dr. Max Wolf (1863-1932), then director of the Heidelberg Observatory. Oskar von Miller, founder of Munich's German Museum, brought Wolf's idea home to Carl Zeiss in 1912/13. Miller wanted to install a heliocentric and a geocentric planetarium at his museum. After some initial difficulties, the breakthrough idea of a projection machine was born that would project the stars, Sun, Moon and the planets from the center of a spherical dome.
The first planetarium on the globe was inaugurated on May 7th, 1925, on the occasion of the opening of a new building of the German Museum. – Today, the German Museum has a planetarium with a Zeiss M 1015 projector. The Model I still exists there; it is on exhibit as a milestone in the history of representing the starry sky.