Callippus

Callippus of Cyzicus (also: Kalippos, Κάλλιπος ) (c. 370 BC in Cyzicus; † 300 BC ) was a Greek astronomer and mathematician.

Callippus was born in Cyzicus on the Marmara Sea and was at the Platonic Academy pupil of Eudoxus. He also worked on the side of Aristotle at the Lyceum.

As a pupil of Eudoxus, he continued his work on the motions of the planets, who had already designed 27 planetary spheres. Callippus felt compelled to introduce seven more; two for the sun, two for the moon and one for Mercury, Venus and Mars. Also calculated according to the Callippus named him Kallippischen cycle ( Metonic cycle).

Named after him are the lunar crater Calippus and Rima Calippus, a groove structure of the Moon.