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liposome

(Encyclopedia)liposome līˈpəsōmˌ, lĭpˈə– [key], microscopic, fluid-filled pouch whose walls are made of layers of phospholipids identical to the phospholipids that make up cell membranes. Liposomes are us...

Teotihuacán

(Encyclopedia)Teotihuacán tāōtēwäkänˈ [key], ancient commercial and religious center in the central valley of Mexico, c.30 mi (48 km) NE of Mexico City. Once thought to be the great religious center of the T...

theory

(Encyclopedia)theory, in music, discipline involving the construction of cognitive systems to be used as a tool for comprehending musical compositions. The discipline is subdivided into what can be called speculati...

mirror

(Encyclopedia)mirror, in optics, a reflecting surface that forms an image of an object when light rays coming from that object fall upon it (see reflection). Usually mirrors are made of plate glass, one side of whi...

day

(Encyclopedia)day, period of time for the earth to rotate once on its axis. The ordinary day, or solar day, is measured relative to the sun, being the time between successive passages of the sun over a stationary o...

Mount Wilson Observatory

(Encyclopedia)Mount Wilson Observatory, astronomical observatory located in California on Mt. Wilson, near Pasadena. Mt. Wilson Observatory was founded in 1904 by George E. Hale. Its equipment includes 100-in. (2.5...

magnitude

(Encyclopedia)magnitude, in astronomy, measure of the brightness of a star or other celestial object. The stars cataloged by Ptolemy (2d cent. a.d.), all visible with the unaided eye, were ranked on a brightness sc...

satellite, natural

(Encyclopedia)satellite, natural, celestial body orbiting a planet, dwarf planet, asteroid, or star of a larger size. The most familiar natural satellite is the earth's moon; thus, satellites of other planets are o...

Newton, Sir Isaac

(Encyclopedia)Newton, Sir Isaac, 1642–1727, English mathematician and natural philosopher (physicist), who is considered by many the greatest scientist that ever lived. Newton was his university's representa...

Foster, Norman Robert, Baron Foster of Thames Bank

(Encyclopedia)Foster, Norman Robert, Baron Foster of Thames Bank, 1935–, British architect, b. Manchester, grad. Manchester Univ. school of architecture (1961), Yale school of architecture (M.A., 1962). Foster an...