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X-ray astronomy

(Encyclopedia)X-ray astronomy, study of celestial objects by means of the X rays they emit, in the wavelength range from 0.01 to 10 nanometers. X-ray astronomy dates to 1949 with the discovery that the sun emits X ...

X-ray crystallography

(Encyclopedia)X-ray crystallography, the study of crystal structures through X-ray diffraction techniques. When an X-ray beam bombards a crystalline lattice in a given orientation, the beam is scattered in a defini...

ray, in zoology

(Encyclopedia)ray, extremely flat-bodied cartilaginous marine fish, related to the shark. The pectoral fins of most rays are developed into broad, flat, winglike appendages, attached all along the sides of the head...

ray, in physics

(Encyclopedia)ray, in physics, term denoting the straight line along which light or other form of radiation is propagated from its source. It generally refers to the line of propagation of waves but is also applied...

cathode-ray tube

(Encyclopedia)CE5 Cathode-ray tube cathode-ray tube (CRT), special-purpose electron tube in which electrons are accelerated by high-voltage anodes, formed into a beam by focusing electrodes, and projected towar...

Baker, Ray Stannard

(Encyclopedia)Baker, Ray Stannard, pseud. David Grayson, 1870–1946, American author, b. Lansing, Mich., grad. Michigan State College (now Michigan State Univ.), 1889. At first a Chicago newspaper reporter, he joi...

Compton Gamma-Ray Observatory

(Encyclopedia)Compton Gamma-Ray Observatory: see gamma-ray astronomy. ...

Heseltine, Michael Ray Dibdin

(Encyclopedia)Heseltine, Michael Ray Dibdin hĕsˈəltīnˌ, hĕzˈ– [key], 1933–, British politician. After studying law at Oxford, he built a successful career in publishing before entering the House of Commo...

Lankester, Sir Edwin Ray

(Encyclopedia)Lankester, Sir Edwin Ray lăngˈkəstər [key], 1847–1929, English zoologist. He was a professor at University College, London (1874–90) and Oxford (1891–98) and was director of the natural hist...

Crab Nebula

(Encyclopedia)Crab Nebula, diffuse gaseous nebula in the constellation Taurus; cataloged as NGC 1952 and M1, the first object recorded in Charles Messier's catalog of nonstellar objects (see Messier catalog). It is...