Aristarchus of Samos

The study of the stars is the oldest of the sciences. The Babylonians observed them systematically 4,000 years before Christ. In Greece in 500 b.c., the Pythagoreans already thought of the earth as a sphere poised in space. And the concept of a solar system with the planets revolving about the sun was put forth about 265 b.c. by Aristarchus of Samos. 

BC Greek astronomer Aristarchus of Samos (c. 320-230 bc) proposes a sun-centred universe. 

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