Aristarchus of samos is the first to suggest a heliocentric system , which mean Sun-in-center of the solar system , before Astronomy everybody thought the earth was in the center of the solar system.
The Greeks know the earth was found before other people. Eratosthenes calcutated the size of the earth hundreds of years before other people. Hipparchus calcuted the lenghth of a month and made a book with names and locations of over 1,000 star’s.
Before the greeks started doing sciencetific things Mesopotamian