James Van Allen

views updated

James Van Allen

1914-

American physicist and space scientist responsible for discovering the radiation belts now named for him. The first successful American artificial satellite, Explorer, was sent into orbit in 1958 carrying a radiation detector. This noted extremely high radiation levels in distinct belts surrounding the Earth. Van Allen discovered the radiation belts and determined they originated from charged particles from the Sun, trapped by Earth's magnetic field.

More From encyclopedia.com