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heat

(Encyclopedia)heat, nonmechanical energy in transit, associated with differences in temperature between a system and its surroundings or between parts of the same system. The study of heat and its relationship ...

radio astronomy

(Encyclopedia)radio astronomy, study of celestial bodies by means of the electromagnetic radio frequency waves they emit and absorb naturally. Radio waves also come from outside the Milky Way. These extragalact...

Ghent

(Encyclopedia)Ghent gĕnt [key], Du. Gent, Fr. Gand, city, capital of East Flanders prov., W Belgium, at th...

European Atomic Energy Community

(Encyclopedia)European Atomic Energy Community (Euratom or EAEC), economic organization that came into being as the 3d treaty organization of what has become the European Union; established by the Treaty of Rome (1...

Environmental Protection Agency

(Encyclopedia)Environmental Protection Agency (EPA), independent agency of the U.S. government, with headquarters in Washington, D.C. It was established in 1970 to reduce and control air and water pollution, noise ...

Mather, John Cromwell

(Encyclopedia)Mather, John Cromwell, 1946–, American astrophysicist, b. Roanoke, Va., Ph.D. Univ. of California, Berkeley, 1974. He has been a researcher at NASA's Goddard Space Flight Center in Greenbelt, Md., s...

cataract

(Encyclopedia)cataract, in medicine, opacity of the lens of the eye, which impairs vision. In the young, cataracts are generally congenital or hereditary; later they are usually the result of degenerative changes b...

Wood, Robert Williams

(Encyclopedia)Wood, Robert Williams, 1868–1955, American physicist, b. Concord, Mass., grad. Harvard (B.A., 1891). After studying abroad he became associated with Johns Hopkins as professor of experimental physic...

Purcell, Edward Mills

(Encyclopedia)Purcell, Edward Mills, 1912–97, American physicist, b. Taylorville, Ill., Ph.D. Harvard, 1938. During World War II, Purcell was a researcher at the Massachusetts Institute of Technology Radiation La...

Brown, Harold

(Encyclopedia)Brown, Harold, 1927–2019, American nuclear physicist and government official, b. New York City, Ph.D. Columbia, 1949. He joined (1952) the staff of the Lawrence Radiation Laboratory (now Lawrence Li...