This model positioned the Sun near the middle of the Universe, motionless, with Earth and the other planets orbiting around it in circular paths, modified by epicycles, and at uniform speeds. The Copernican model displaced the geocentric model of Ptolemy that had prevailed for hundreds of years, which had placed Earth on the center of the Universe.
In truth, around the same time as Galileo, one other astronomer named Johannes Kepler was also engaged on heliocentrism. Using the detailed observations of his mentor and famous astronomer in his personal right, Tycho Brahe, Kepler was capable of decide that the planets within the photo voltaic system had elliptical orbits around the Sun. This was an enchancment to the heliocentric model developed by Copernicus, who had nonetheless believed planets orbit in excellent circles when he developed it. The incontrovertible fact that planets orbit the sun in ellipses turned the first of Kepler’s … Read MoreRead More »