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Van Allen radiation belts

(Encyclopedia)CE5 Van Allen radiation belts: The solar wind, a stream of protons, electrons, and ions coming from the sun, gives the belts their asymmetrical shape. Van Allen radiation belts, belts of radiation...

Van Allen, James Alfred

(Encyclopedia)Van Allen, James Alfred, 1914–2006, American physicist and space scientist, Mt. Pleasant, Iowa. A graduate (Ph.D 1939) of and professor of physics (1951–85) at what is now the Univ. of Iowa, where...

radiation

(Encyclopedia)radiation rāˌdēāˈshən [key], term applied to the emission and transmission of energy through space or through a material medium and also to the radiated energy itself. In its widest sense the te...

magnetosphere

(Encyclopedia)magnetosphere: see Van Allen radiation belts. ...

Orbiting Solar Observatory

(Encyclopedia)Orbiting Solar Observatory (OSO), series of eight orbiting observatories (see observatory, orbiting) launched between 1962 and 1971 by the National Aeronautics and Space Administration (NASA) to study...

ionosphere

(Encyclopedia)ionosphere īŏnˈəsfēr [key], series of concentric ionized layers forming part of the upper atmosphere of the earth from around 30 to 50 mi (50 to 80 km) to 250 to 370 mi (400 to 600 km) where it m...

International Geophysical Year

(Encyclopedia)International Geophysical Year (IGY), 18-month period from July, 1957, through Dec., 1958, during a period of maximum sunspot activity, designated for cooperative study of the solar-terrestrial enviro...

aurora borealis

(Encyclopedia)aurora borealis ôstrāˈlĭs [key], luminous display of various forms and colors seen in the night sky. The aurora borealis of the Northern Hemisphere is often called the northern lights, and the aur...

electromagnetic radiation

(Encyclopedia)CE5 Electromagnetic spectrum electromagnetic radiation, energy radiated in the form of a wave as a result of the motion of electric charges. A moving charge gives rise to a magnetic field, and if ...

Cherenkov radiation

(Encyclopedia)Cherenkov radiation or Cerenkov radiation [for P. A. Cherenkov], light emitted by a transparent medium when charged particles pass through it at a speed greater than the speed of light in the medium. ...