bands of radiation trapped in Earth's magnetic field, which both absorb ambient deep-space radiation and provide protection for Earth's surface, and are a hazard for satellites and humans operating within them
Two doughnut-shaped zones of radiation about the Earth, concentrated at altitudes of 3,000 and 10,000 miles; named after James A. Van Allen who instrumented the satellite Explorer I. The belts contain charged particles generated by solar flares and trapped by the Earth's magnetic field.