Picture of Ptolemy
The Bettmann Archive
Ptolemy was a Greek astronomer who lived between 85-165 A.D. He put together his own ideas with those of Aristotle and Hipparchus and formed a unified model of the universe. Ptolemy believed that the Earth was at the center of the universe and all other heavenly bodies circled it, a view which held for 1400 years until the time of Copernicus.
Ptolemy is also famous for his work in geography.
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