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Brahic, André Fernand

(Encyclopedia)Brahic, André Fernand, 1942–2016, French astrophysicist, b. Paris. He was introduced to astrophysics by Evry Schatzman, a leading French theoretician, and obtained his doctorate from the Univ. of P...

Sacrobosco, Johannes de

(Encyclopedia)Sacrobosco, Johannes de yōhänˈəs də săkrōbŏsˈkō [key], or John of Hollywood, c.1200–1256, English mathematician and astronomer. He wrote several widely read and influential books: Algorism...

Benedetti, Giovanni Battista

(Encyclopedia)Benedetti, Giovanni Battista jōvänˈnē bät-tēsˈtä bānādĕtˈtē [key], 1530–90, Italian mathematician and physicist. An important forerunner of Galileo, Benedetti had diverse interests, inc...

Galle, Johann Gottfried

(Encyclopedia)Galle, Johann Gottfried yōˈhän gôtˈfrēt gäˈlə [key], 1812–1910, German astronomer. He is noted for his discovery of the planet Neptune, Sept. 23, 1846, by following the guidance of calculat...

Mauna Kea Observatories

(Encyclopedia)Mauna Kea Observatories mouˈnə kāˈə [key], astronomical observatory complex located on Mauna Kea peak, the “white mountain” on the island of Hawaii, at an altitude of more than 13,600 ft (4,1...

Al-Farghani

(Encyclopedia)Al-Farghani ălfrəgāˈnəs [key], d. after 861, Arab astronomer. Al-Farghani was born in Farghana, Transoxania (present-day Fergana, Uzbekistan), and died in Egypt. His most important work, written ...

hour circle

(Encyclopedia)hour circle, in astronomy, a secondary axis in the equatorial coordinate system. The hour circle of a celestial body is the great circle on the celestial sphere that passes through both the body and t...

Picard, Jean

(Encyclopedia)Picard, Jean, 1620–82, French astronomer, noted for having made the first accurate measurement of a degree of the earth's meridian. The figures he established were of great value to Newton in his ca...

light-year

(Encyclopedia)light-year, in astronomy, unit of length equal to the distance light travels in one sidereal year. It is 9.461 × 1012 km (about 6 million million mi). Alpha Centauri and Proxima Centauri, the stars n...

Brahmagupta

(Encyclopedia)Brahmagupta bräˌməgo͝opˈtə [key], c.598–c.660, Indian mathematician and astronomer. He was among the first to meaningfully discuss the concepts of zero and of negative numbers. He wrote in ver...
 

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