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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 ...

observatory

(Encyclopedia)observatory, scientific facility especially equipped to detect and record naturally occurring scientific phenomena. Although geological and meteorological observatories exist, the term is generally ap...

relativity

(Encyclopedia)relativity, physical theory, introduced by Albert Einstein, that discards the concept of absolute motion and instead treats only relative motion between two systems or frames of reference. One consequ...

Delors, Jacques

(Encyclopedia)Delors, Jacques (Jacques Lucien Jean Delors) zhäk lo͞osyăNˈ zhäN dəlôrˈ [key] 1925–, French economist and politician and European statesman, president (1985–95) of the European Commission....

empyema

(Encyclopedia)empyema ĕmpē-ēˈmə [key], persistent purulent discharge into a cavity such as the pleural space or the gallbladder. Empyema results as a complication of bacterial infections such as pneumonia and ...

Bourget, Le

(Encyclopedia)Bourget, Le, town, Seine–Saint-Denis dept., N central France. A suburb of Paris, it is the site of Le Bourget airport, once Paris's main airport but n...

Steer, Philip Wilson

(Encyclopedia)Steer, Philip Wilson, 1860–1942, English landscape painter. Steer worked largely in the tradition of French impressionist painting and was considered the greatest English landscape painter of his da...

Schuman, Robert

(Encyclopedia)Schuman, Robert rōbĕrˈ sho͞omäNˈ [key], 1886–1963, French statesman and lawyer, b. grand duchy of Luxembourg. A member of the Catholic Mouvement Républicain Populaire (MRP), he was finance mi...

International Refugee Organization

(Encyclopedia)International Refugee Organization (IRO), temporary agency of the United Nations, established in 1946. In arranging for the care and the repatriation or resettlement of Europeans made homeless by Worl...

National Institute of Standards and Technology

(Encyclopedia)National Institute of Standards and Technology, governmental agency within the U.S. Dept. of Commerce with the mission of “working with industry to develop and apply technology, measurements, and st...