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planetary science

(Encyclopedia)planetary science or planetology, study of planets and planetary systems as a whole. Planetary science applies the theories and methods of traditional disciplines such as astronomy, geology, physics, ...

celestial mechanics

(Encyclopedia)celestial mechanics, the study of the motions of astronomical bodies as they move under the influence of their mutual gravitation. Celestial mechanics analyzes the orbital motions of planets, dwarf pl...

blood count

(Encyclopedia)blood count, method for determining the number of red (erythrocytes) and white (leukocytes) blood cells in a certain volume of blood. This test can be used as a preliminary step in diagnosing some dis...

Saint Bernard, breed of dog

(Encyclopedia)Saint Bernard, breed of massive working dog developed in Switzerland in the 18th cent. and perfected by British breeders during the 19th cent. It stands from 25 to 29 in. (64–74 cm) high at the shou...

English setter

(Encyclopedia)English setter, breed of large sporting dog developed over hundreds of years in England. It stands about 25 in. (63.5 cm) high at the shoulder and weighs about 60 lb (27.2 kg). Its flat or slightly wa...

Slocum massacre

(Encyclopedia)Slocum massacre, July 29–30, 1910, killing of an unknown number of African Americans by armed mobs of white men in the town of Slocum, Texas. The killings may have been precipitated by rumors that b...

jackrabbit

(Encyclopedia)jackrabbit, popular name for several hares of W North America, characterized by very long legs and ears. Jackrabbits are powerful jumpers and fast runners. In normal progress leaps are alternated with...

horehound

(Encyclopedia)horehound, aromatic Old World perennial herb (Marrubium vulgare) of the family Labiatae (mint family), naturalized in North America. It has woolly white foliage and tiny white clustered flowers and is...

Milky Way

(Encyclopedia)CE5 Position of the sun in the Milky Way Milky Way, the galaxy of which the sun and solar system are a part, seen as a broad band of light arching across the night sky from horizon to horizon; if ...

pyroxene

(Encyclopedia)pyroxene pīˈrŏksēn [key], name given to members of a group of widely distributed rock minerals called metasilicates in which magnesium, iron, and calcium, often with aluminum, sodium, lithium, man...