Who is considered the greatest ancient Greek astronomer?
Hipparchus (fl. 190-120 B.C.), who lived about 100 years after Aristotle, is considered to have been the greatest ancient Greek astronomer (a scientist specializing in the study of matter in outer space). Hipparchus was the first to develop a detailed explanation of how the planets and other objects move throughout the solar system. He was mistaken, however, as were most astronomers of the day, in placing the Earth (rather than the sun) at the center of the solar system. Hipparchus measured, with remarkable accuracy, the directions of objects in the sky. He compiled the first catalog of stars, containing about 850 entries. He recorded each star’s celestial coordinates, indicating its position in the sky. Hipparchus also categorized the stars according to their apparent brightness, or magnitudes. One of Hipparchus’s greatest…
