Aristarchus of Samos (310 BC - c 230 BC)

Aristarchus was a Greek astronomer and mathematician. Though Copernicus is given credit for the heliocentric model, Aristarchus was actually the first who considered a model with the sun at the center of the universe. His only known surviving work is On the Sizes and Distances of the Sun and Moon. In it he used correct geometry but incorrect geodetic data to conclude that the sun was 18 to 20 times farther away than the moon.

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Stamps

Stamp	Description
	Greece, 10d, 1980 Scott: 1350 A436
	Greece, 20d, 1980 Scott: 1351 A436