Aboriginals realised that the Southern Cross can be used for navigation using Dreamtime stories.
Ptolemy developed a model that predicted the movements of the Sun, Moon, planets and stars.Correctly predicted a solar eclipse and brought lots of astronomical information from other cultures to Greece.
Jan 1, 821
Al-Khwarismi was the creator of Algebra.
Jan 1, 1076
Omar Khayyam created the pre-Gregorian calendar and calculated today's year.
Mar 21, 1492
Copernicus made the heliocentric model