1.    1543 De revolutionibus orbium coelestium was published. Copernicus lays out the Copernican heliocentrism, an astronomical model that puts the sun at the center of the universe.  Copernicus describes the sun as sitting motionless at the center as the earth and other planets rotate around it in circular paths.  Copernicus dedicated the book to Pope Paul III, hoping to gain favor from the church.  This file is licensed under the Creative Commons Attribution Share Alike 3.0 Uported License.