CEGHINT Timeline By KFCGuardian 100 Claudius Ptolemy created a model of the movement of the planets and moons Created a model of the movement of the planets and moons Period: 100 to Mar 27, 2015 Astronomy Timeline May 10, 1543 Copernicus decides Sun is center of universe Nov 20, 1572 Tycho Brahe observed and recorded a super nova Mar 25, 1632 Galileo publishes his GaliLIES Oct 14, 1684 Isaac Newton published his book on Mathematical Principles of Natural History Aug 12, 1908 Henrietta Leavitt published her paper on period-luminosity Jun 7, 1924 Edwin Hubble proved that galaxies exist besides our own