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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...

tetanus

(Encyclopedia)tetanus tĕtˈnəs, –ənəs [key] or lockjaw, acute infectious disease of the central nervous system caused by the toxins of Clostridium tetani. The organism has a widespread distribution and is com...

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...

marines

(Encyclopedia)marines, troops that serve on board ships of war or in conjunction with naval operation. A British marine corps was established in 1664, and the need for skilled riflemen aboard military vessels broug...

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...
 

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