Johannes Kepler

One of the founders of modern astronomy who discovered the three basic laws of planetary motion, amongthem that planetary orbits are elliptical. He introduced several minor aspects including the bi-quintile (144°), tredecile (108°), quintile (fifth harmonic, 72°), decile or semi-quintile (36°), quindecile (24°) and the semidecile or vigintile (18°).