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fullerene

(Encyclopedia)fullerene, any of a class of carbon molecules in which the carbon atoms are arranged into 12 pentagonal faces and 2 or more hexagonal faces to form a hollow sphere, cylinder, or similar figure. The sm...

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...

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...

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...

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...

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...

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...

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...

materialism

(Encyclopedia)materialism, in philosophy, a widely held system of thought that explains the nature of the world as entirely dependent on matter, the fundamental and final reality beyond which nothing need be sought...