Babylonian astronomy refers to the astronomy that eveloped in Mesopotamia, the "land between the rivers" Tigris and Euphrates, corresponding to modern-day Iraq, where the ancient kingdoms of Sumer, Akkad, Assyria, Babylonia and Chaldea were located. Babylonian astronomy was the basis for much of the astronomical traditions that later developed in Greek and Hellenistic astronomy, in classical Indian astronomy, in Sassanid, Byzantine and Syrian astronomy, in medieval Islamic astronomy, and in Western European astronomy.