Almagest

The Almagest is a classical astronomical text written by the ancient Greek scholar Claudius Ptolemy in the 2nd century. It serves as a comprehensive guide to the geocentric model of the universe, where Earth is at the center, and describes the movements of celestial bodies, such as the sun, moon, and planets. The work laid the foundation for astronomy in the Western world for over a thousand years and includes mathematical methods for predicting the positions of stars and planets. Its influential ideas shaped medieval and Renaissance astronomy until the heliocentric model emerged.