Van Allen, James

Van Allen, James (Alfred)

(1914– ) physicist; born in Mount Pleasant, Iowa. Educated at Iowa Wesleyan and the University of Iowa, he was a fellow in nuclear physics at the Carnegie Institution of Washington's department of terrestrial magnetism (1939–41). He spent several years at Johns Hopkins University in the 1940s before returning to head the department of physics and astronomy at the University of Iowa (1951). As one of the major planners of the International Geophysical Year (1957–58), he proposed the experiment that, using data from the Explorer I and Pioneer III space probes of the region known as the magnetosphere, revealed the existence of the radiation belts—concentrations of electrically charged particles known since as "the Van Allen belts." He was the principal investigator on 23 other space probes and in 1989 he was awarded the Crafoord Prize.