EESC 1175 Lecture Notes - Ptolemy, Nicolaus Copernicus, Geocentric Model
Document Summary
Put under house arrest for the last 10 years of his life. Motion of the planets: according to greek studies (600 bc 150 bc: geocentric = earth was in the center of the universe, the earth was believed to be spherical, motionless and surrounded by the. Stars hung on the celestial sphere and were carried on a daily trip around the earth (ex. the stars rise and set like the sun and moon) Except for seven objects (sun, moon, wanderers: and 5: claudius ptolemy. Wanderer = greek word for planet: ptolemaic system = the geocentric model of the universe (141 bc) Problem retrograde motion of the planets: planets moved eastward against the background of the stars, but occasionally they appeared to stop, reverse direction for several weeks, then resume in eastward motion. Solution epicycle = each planet"s small circular path. Deferent = the larger circular path that a planet takes while it orbits around another object.