Seleucus of Seleucia

https://en.wikipedia.org/wiki/Seleucus_of_Seleucia

Seleucus of Seleucia (Greek: Σέλευκος Seleukos; c. 190 BC - c. 150 BC) was a Hellenistic astronomer and philosopher. Coming from Seleucia on the Tigris, Mesopotamia, the capital of the Seleucid Empire, or, alternatively, Seleukia on the Erythraean Sea, he is best known as a proponent of heliocentrism and for his theory of the origin of tides.