ARISTARCO da SAMO. - Greek mathematician and astronomer, who lived between 310 and 230 B.C. He had
the great merit of formulating and defending the same hypotheses that underlie the system rediscovered 18 centuries later by Copernico: namely, that the fixed stars and the sun are immobile, and that the earth revolves around its axis and moreover describes a circle of which the sun is the centre. It follows that the sun is much farther from the earth than the moon, and that the fixed stars are at a very great distance from the sun and the earth. This theory, already intuited by Eraclele da Ponto, made the cosmogonic conceptions of the ancient Babylonians, Egyptians, and Greeks appear paltry. Astrologers, says Schiaparelli, “sought with all their strength to suppress a theory that was bound to overthrow all their pretences.” Plutarco (De Facie in Orbe Lunae) reports that Cleante had accused A. of impiety.
Archimede described A.’s theories in his Arenario. Seneca (Nat. Quaest., VII, 2) referred to it as: digna res est contemplatione ut sciamus in quo rerum statu simus.