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satellite, artificial

(Encyclopedia)CE5 A. Nimbus weather satellite B. Syncom communications satellite satellite, artificial, object constructed by humans and placed in orbit around the earth or other celestial body (see also space ...

diffusion

(Encyclopedia)diffusion, in chemistry, the spontaneous migration of substances from regions where their concentration is high to regions where their concentration is low. Diffusion is important in many life process...

Sperry, Elmer Ambrose

(Encyclopedia)Sperry, Elmer Ambrose, 1860–1930, American inventor, b. Cortland, N.Y. Although probably best known for his work on the gyroscope, he also invented the gyrocompass (1910), an extremely effective hig...

radar

(Encyclopedia)radar, system or technique for detecting the position, movement, and nature of a remote object by means of radio waves reflected from its surface. Although most radar units use microwave frequencies, ...

Akron, University of

(Encyclopedia)Akron, University of, at Akron, Ohio; coeducational; established 1870 as Buchtel College, transferred 1913 as the nucleus of the Municipal Univ. of Akron. In 1967 the school became a state university....

Alvord, Henry Elijah

(Encyclopedia)Alvord, Henry Elijah, 1844–1904, American agriculturist, educator, and specialist in dairy husbandry, b. Greenfield, Mass. He pioneered in developing the cooperative creamery system and served (1886...

Hamitic languages

(Encyclopedia)Hamitic languages, subfamily of the Hamito-Semitic family of languages, a now-abandoned system of classification for languages of N Africa and SW Asia. The Egyptian, Berber, Cushitic, and (sometimes) ...

American Samoa, The National Park of

(Encyclopedia)American Samoa, The National Park of, c.9,000 acres (3,645 hectares), American Samoa, S Pacific Ocean. Comprising areas on the islands of Ofu, Ta'u, and Tutuila, the park features the only paleotropic...

Meurthe

(Encyclopedia)Meurthe mört [key], river, c.105 mi (169 km) long, rising in the Vosges, NE France, and flowing NW past Lunéville to join the Moselle River just N of Nancy. Its very irregular level has necessitated...

Msta

(Encyclopedia)Msta əmstäˈ [key], river, c.280 mi (450 km) long, rising N of Vyshne Volochek, NW European Russia, and flowing generally NW into Lake Ilmen near Novgorod. Navigable in its lower course, it is inclu...