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radiometer

(Encyclopedia)radiometer rāˌdēŏmˈətər [key], instrument for detection or measurement of electromagnetic radiation; the term is applied in particular to devices used to measure infrared radiation. One of the ...

Magellanic Clouds

(Encyclopedia)Magellanic Clouds măjˌəlănˈĭk [key], two dwarf galaxies located in the far southern sky and visible to the unaided eye; they are classified as irregular because they show no definite symmetry or...

nebula

(Encyclopedia)nebula nĕbˈyo͝olə [key] [Lat.,=mist], in astronomy, observed manifestation of a collection of highly rarefied gas and dust in interstellar space. Prior to the 1960s this term was also applied to b...

Walker, Herschel Junior

(Encyclopedia)Walker, Herschel Junior, 1962–, American football player, b. Wrightsville, Ga. After winning the 1982 Heisman Trophy, as college football's best player, at the Univ. of Georgia, he played (1983–85...

Glenn, John Herschel, Jr.

(Encyclopedia)Glenn, John Herschel, Jr., 1921–2016, American astronaut and politician, b. Cambridge, Ohio. On Feb. 20, 1962, he became the first American and the third person to orbit the earth, circling the glob...

Johnson, Herschel Vespasian

(Encyclopedia)Johnson, Herschel Vespasian, 1812–80, U.S. political leader, b. Burke co., Ga. Admitted to the bar in 1834, he filled (1848–49) an unexpired Senate term before serving as circuit court judge (1849...

infrared astronomy

(Encyclopedia)infrared astronomy, study of celestial objects by means of the infrared radiation they emit, in the wavelength range from about 1 micrometer to about 1 millimeter. All objects, from trees and building...

infrared radiation

(Encyclopedia)infrared radiation, electromagnetic radiation having a wavelength in the range from c.75 × 10−6 cm to c.100,000 × 10−6 cm (0.000075–0.1 cm). Infrared rays thus occupy that part of the electrom...

Hazlitt, William

(Encyclopedia)Hazlitt, William, 1778–1830, English essayist. The son of a reform-mindeed Unitarian minister, he abandoned the idea of entering the clergy and took up painting, philosophy, and later journalism. He...

fingerprint

(Encyclopedia)fingerprint, an impression of the underside of the end of a finger or thumb, used for identification because the arrangement of ridges in any fingerprint is thought to be unique and permanent with eac...
 

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