Ptolemy

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Ptolemy (ad 90–168) ( Claudius Ptolemaeus) Greek astronomer and geographer. He worked at the library of Alexandria, Egypt. Ptolemy's chief astronomical work, the Almagest, drew heavily on the work of Hipparchus. The Ptolemaic system is based on the geocentric world system of the ancient Greeks. His Geography, which provided the basis for a world map, was a definitive text until the Renaissance.

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