c. 310-c. 230 B.C.

Greek Astronomer and Mathematician

Aristarchus is famous for developing the first heliocentric planetary theory. For this, he has come to be known as the "Copernicus of antiquity." He also made the first rational estimates of the distance to the Sun and Moon as well as the size of those bodies.

Very little is known of Aristarchus's personal life. He was born on the Aegean island of Samos sometime around 310 B.C. He made his way to Alexandria sometime before 287 B.C. There he studied under Strato of Lampsacus (d. c. 270 B.C.). His only surviving work is On the Size and Distances of the Sun and Moon. The details of his heliocentric theory were preserved by Archimedes (287-212 B.C.) in The Sand-Reckoner.

Aristarchus was first to attempt a determination of astronomical distances and dimensions by geometrical analysis. The basis...