Hipparchus in his observatory in Alexandria. In the centre is an armillary sphere. Hipparchus (190-120 BC), was a Greek astronomer, geographer, and mathematician of the Hellenistic period. A methodical observer, Hipparchus compiled the first known star catalogue, listing some 850 stars, as well as their celestial coordinates and magnitude. His work profoundly influenced that of Ptolemy. He is considered the founder of trigonometry. Hipparchus is considered the greatest ancient astronomical observer. He was the first whose quantitative and accurate models for the motion of the Sun and Moon survive. He developed trigonometry and constructed trigonometric tables, and he solved several problems of spherical trigonometry. With his solar and lunar theories and his trigonometry, he may have been the first to develop a reliable method to predict solar eclipses. This image has been colour enhanced. | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Science Source / New York Public Library |
Bildgröße: | 4200 px × 2565 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
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