The Almagest is an influential, 2nd-century astronomical treatise written by Claudius Ptolemy in Greek, which was translated into Arabic and given the name "Almagest," meaning "The Greatest". It presented a geocentric model of the universe, where Earth is at the center, and remained the authoritative astronomical text for over 1,200 years. The work provides detailed mathematical models for calculating the positions of the Sun, Moon, and planets, and its accurate predictions of celestial motions were based on both Babylonian and Greek mathematical astronomy.
