Van Allen radiation beltVan Al·len radiation belt
either of two broad, doughnut-shaped regions surrounding the earth and composed of high-energy electrons and protons trapped in the earth's magnetic field at heights between c. 400 km (c. 250 mi) and c. 64,370 km (c. 40,000 mi)
Origin of Van Allen radiation beltafter James A. Van Allen (1914-2006), United States physicist
(plural Van Allen radiation belts)
- (astronomy, physics) Either of two torus-shaped areas of high-energy charged particles which partly surround Earth, trapped by its magnetic field. The areas are characterised by intense radiation. When the belts "overload", particles strike the upper atmosphere and fluoresce, causing the polar aurora.
From James Alfred Van Allen, US physicist.