Around 150 CE, Claudius Ptolemy, a Greco-Egyptian astronomer working in Alexandria, compiled the Mathematike Syntaxis (later known as the Almagest, from Arabic "al-majisti" meaning "the greatest"). This comprehensive astronomical treatise presented a geocentric model of the universe with the Earth at the center and celestial bodies moving in complex combinations of circles (epicycles and deferents). Despite being fundamentally wrong about the Earth's position, the Ptolemaic model was remarkably accurate at predicting planetary positions and eclipses. It remained the dominant astronomical framework until Copernicus proposed the heliocentric model in the 16th century.
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