Name: Aristarchus of Samos
Lived: c. 310–230 BC, Samos, Greece
Known for: Ancient Greek astronomer and mathematician
Famous for: First to propose a heliocentric model of the solar system (recorded by Archimedes); in his surviving work, On the Sizes and Distances of the Sun and Moon, he used geometry to estimate their relative sizes and distances.
Note: Aristarchus proposed a heliocentric model, recorded by Archimedes, where Earth orbits the Sun. Though that work is lost, his surviving text, On the Sizes and Distances of the Sun and Moon, revealed the Sun’s vast size.