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photonics

(Encyclopedia)photonics, the science and technology based on and concerned with the controlled flow of photons, or light particles. It is the optical equivalent of electronics, and the two technologies coexist in s...

Wineland, David Jeffrey

(Encyclopedia)Wineland, David Jeffrey, 1944–, American physicist, b. Milwaukee, Wis., Ph.D. Harvard, 1970. Wineland has been a researcher at the National Institute of Standards and Technology and the Univ. of Col...

meteor

(Encyclopedia)meteor, appearance of a small particle flying through space that interacts with the earth's upper atmosphere. While still outside the atmosphere, the particle is known as a meteoroid. Countless meteor...

International Geophysical Year

(Encyclopedia)International Geophysical Year (IGY), 18-month period from July, 1957, through Dec., 1958, during a period of maximum sunspot activity, designated for cooperative study of the solar-terrestrial enviro...

teacher training

(Encyclopedia)teacher training, professional preparation of teachers, usually through formal course work and practice teaching. Although the concept of teaching as a profession is fairly new, most teachers in indus...

Rumford, Benjamin Thompson, Count

(Encyclopedia)Rumford, Benjamin Thompson, Count, 1753–1814, American-British scientist and administrator, b. Woburn, Mass. In 1776 he went to England, where he served (1780–81) as undersecretary of the colonies...

sea lily

(Encyclopedia)sea lily, stalked echinoderm of the class Crinoidea. Sea lilies are ancient, having reached their peak in the Middle Mississippian period; about 5,000 fossil species are known. About 80 modern species...

gegenschein

(Encyclopedia)gegenschein gāˈgənshīnˌ [key] or counterglow, a slight brightening of the night sky in the region of the zodiac directly opposite the sun, i.e., 180° from the sun. Discovered by the Danish astro...

Fitch, Val Logsdon

(Encyclopedia)Fitch, Val Logsdon, 1923–2015, American nuclear physicist, b. Merriman, Neb., Ph.D. Columbia, 1954. During World War II Fitch was drafted into the army and worked on the detonator for the atomic bom...

homogenization

(Encyclopedia)homogenization həmŏjˌənəzāˈshən [key], process in which a mixture is made uniform throughout. Generally this procedure involves reducing the size of the particles of one component of the mixtu...