- Aristarchus of Samos
*(c. 320 bc– c. 250 bc) Greek astronomer*Little is known of the life of Aristarchus, but Archimedes reported that Aristarchus had proposed that, while the Sun and the fixed stars are motionless, the Earth moves around the Sun on the circumference of a circle. Just what led Aristarchus to this view and how firmly he held it is not known. It received no support until the late medieval period.One short work of Aristarchus has survived –*On the Sizes and Distances of the Sun and Moon*. In this work he calculated that the Earth is about 18 times further away from the Sun than from the Moon. His method was to use the fact that when the Moon is exactly in the second quarter it will form a right-angled triangle with the Earth and the Sun, and the relative lengths of the sides of the triangle can be determined by angular measurement. Although Aristarchus's method is correct, his measurement was inaccurate (the Sun is roughly 400 times further away). Despite the size of the error it was nevertheless the first attempt to come to grips with astronomical distances by something more sophisticated than revelation or guesswork.

*Scientists.
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2011.*

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**Aristarchus of Samos**— Aristarchus, or more correctly Aristarchos (Greek: Ἀρίσταρχος, Arístarchos; 310 BC – ca. 230 BC), was a Greek astronomer and mathematician, born on the island of Samos, in Greece. He presented the first known heliocentric model of the solar… … Wikipedia**Aristarchus of Samos**— [ar΄is tär′kəs] fl. 3d cent. B.C.; Gr. astronomer * * * born с 310 BC died с 230 BC Greek astronomer. His advanced ideas on the movement of the Earth (which he asserted revolved around the Sun) are known from Archimedes and Plutarch. His only… … Universalium**Aristarchus of Samos**— [ar΄is tär′kəs] fl. 3d cent. B.C.; Gr. astronomer … English World dictionary**Aristarchus of Samos**— biographical name circa 310 230 B.C. Greek astronomer … New Collegiate Dictionary**Aristarchus of Samos**— /ˈseɪmɒs/ (say saymos) noun c. 310–230 BC, Greek astronomer and mathematician; exponent of the theory of a sun centred universe … Australian English dictionary**Aristarchus of Samos**— noun an ancient Greek astronomer who was one of the first to propose a heliocentric theory of the universe (circa 270 BC) • Instance Hypernyms: ↑astronomer, ↑uranologist, ↑stargazer … Useful english dictionary**Aristarchus On the Sizes and Distances**— Aristarchus s 3rd century BC calculations on the relative sizes of, from left, the Sun, Earth and Moon, from a 10th century CE Greek copy On the Sizes and Distances (of the Sun and Moon) (Περὶ μεγεθῶν καὶ ἀποστημάτων [ἡλίου καὶ σελήνης]) is… … Wikipedia**Aristarchus**— may refer to: * Aristarchus (crater), on the moon * Aristarchus of Samos (circa 310 230 BC), Greek astronomer and mathematician * Aristarchus of Samothrace (circa 220 143 BC), Greek grammarian * Aristarchus of Tegea (5th century BC), Greek writer … Wikipedia**Aristarchus [1]**— Aristarchus, von Samos, berühmter Astronom, der die Umdrehung der Erde um die eigene Axe und die Jahresbewegung um die Sonne lehrte, lebte in der 2. Hälfte des 3. Jahrh. v. Chr. Von seinen Schriften ist nur die kleine übrig: »Von der Größe und… … Herders Conversations-Lexikon**Aristarchus (crater)**— lunar crater data caption=Aristarchus (center) and Herodotus (right) from Apollo 15. NASA photo . latitude=23.7 N or S=N longitude=47.4 E or W=W diameter=40 km depth=3.7 km colong=48 eponym=Aristarchus of SamosAristarchus is a prominent lunar… … Wikipedia