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polarization of light

(Encyclopedia)polarization of light, orientation of the vibration pattern of light waves in a singular plane. Unpolarized light can be converted into a single polarized beam by means of the Nicol prism, a device ...

observatory, orbiting

(Encyclopedia)observatory, orbiting, research satellite designed to study solar radiation, electromagnetic radiation from distant stars, the earth's atmosphere, or the like. Because the atmosphere and other aspects...

virtual observatory

(Encyclopedia)virtual observatory, a collection of integrated astronomical data archives and software tools that utilize computer networks to create an environment in which research can be conducted. Several countr...

neutron star

(Encyclopedia)neutron star, extremely small, extremely dense star, with as much as double the sun's mass but only a few miles in radius, in the final stage of stellar evolution. Astronomers Baade and Zwicky predict...

bremsstrahlung

(Encyclopedia)bremsstrahlung brĕmˈshträˌləng [key]: see X ray. ...

Fridley

(Encyclopedia)Fridley, city (2020 pop. 29,590), Anoka co., SE Minn., a suburb north of Minneapolis, on the Mississippi River; settled 1847, inc. as a city 1957. A dis...

Orbiting Astronomical Observatory

(Encyclopedia)Orbiting Astronomical Observatory (OAO), series of four orbiting observatories (see observatory, orbiting) launched between 1966 and 1972 by the National Aeronautics and Space Administration (NASA) to...

bichir

(Encyclopedia)bichir bĭchˈər [key], common name for African freshwater fishes as of the family Polypteridae, and particularly for those of the genus Polypterus. Bichirs are among the most primitive of the ray-fi...

Coolidge, William David

(Encyclopedia)Coolidge, William David, 1873–1975, American physical chemist, b. Hudson, Mass., grad. Massachusetts Institute of Technology, 1896. He joined the General Electric Company in 1905 and served as direc...

cosmic rays

(Encyclopedia)cosmic rays, charged particles moving at nearly the speed of light reaching the earth from outer space. Primary cosmic rays consist mostly of protons (nuclei of hydrogen atoms), some alpha particles (...