Hobbies And Interests
Astronomy
The concept of a sky shaped like a sphere has been around since 2000 B.C. in China. However, it was Eudoxus of Cnidos from Greece who created the first known complete celestial globe. Since ancient times, astronomers have been curious about celestial spheres that show information about the stars and the planetariums that can house these celestial spheres.
Planetarium
The first structure to become a large planetarium projector was Carl Zeiss' geodesic dome built on the roof of his optical works in Jena, Germany, in 1922. This lightweight steel structure and the projector used were invented by Dr. Walter Bauersfeld. Both the planetarium and projector created the illusion of a celestial sky indoors by placing stars and other celestial bodies against the inside of the dome.
Celestial Sphere
The celestial sphere is what is projected onto a planetarium's roof or against a simple planetarium like a globe. The artificial celestial sphere is usually hemispherical and contains all the celestial bodies that would normally be seen at night. Earth's natural celestial sphere is everything an observer can see from the surface of the earth.