Columbia Encyclopedia

(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 ...

(Encyclopedia) gamma-ray astronomy, study of astronomical objects by analysis of the most energetic electromagnetic radiation they emit. Gamma rays are shorter in wavelength and hence more energetic than X rays (see...

(Encyclopedia) Barkla, Charles Glover glŭˈvər bärˈklə [key], 1877–1944, English physicist. He was professor of natural philosophy at Edinburgh from 1913. For his discovery of the characteristic X rays of ele...

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

(Encyclopedia) Nagin, Ray (Clarence Ray Nagin, Jr.), 1956–, African-American politician, b. New Orleans. A Louisiana cable-television executive before entering politics, Nagin won the 2002 mayoral election handily...

(Encyclopedia) Palmer, Ray, 1808–87, American Congregational clergyman and hymn writer, b. Little Compton, R.I., grad. Yale, 1830. He held pastorates in Bath, Maine (1835–50), and Albany, N.Y. (1850–66). He is...

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

(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...

(Encyclopedia) Bradbury, Ray (Raymond Douglas Bradbury) brădˈbĕrˌē, –bərē [key], 1920–2012, American writer, b. Waukegan, Ill. A popular and prolific writer of science fiction who did much to bring the ge...

(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...