two millennia until eventually succumbing to the heliocentric or Sun-centered theory of Nicholas Copernicus, Johannes Kepler and Galileo Galilei. Aristarchus (Samos, ca. 320–ca. 250 B.C.E.) Aristarchus is credited as the first to propose the heliocentric model of the cosmos, seventeen centuries before Copernicus resurrected the theory. He suggested that the Earth