Regions of of high-energy particles traped by the magnetic influence of the Earth. These belts are sometimes called "Van Allen" belts because of their discovery in 1958 by Professor J.A. Van Allen. Radiation belts are composed of electrons, protons, and smaller numbers of other ions.
In a planet's magnetosphere, regions with a high density of trapped solar wind particles.
(Also called Van Allen radiation belts.) Belts of energetic electrons, protons, and heavier ions encircling the earth and trapped in the geomagnetic field. The radiation belts are characterized by intense fluxes of high-energy radiation, creating a dangerous environment for spacecraft. The particle density and energy spectrum, as well as the physical characteristics of the belts, depend on the level of solar activity.