Aristarchus(c. 310-250 BC)Astronomer from Samos that was first to conclude that the earth revolves around the sun. This almost cost him his life since it was considered to be offending the gods.

He also created a method of measuring distances of the sun and the moon from the earth. The method was basically correct, but his results wrong because of lack of accurate instruments.

The only surviving work of Aristarchus is "On the Dimensions" and "Distances of the Sun and Moon". The rest of his work we know about through the writings of Archimedes.