Van Allen belt

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Van Allen belt Two belts of high-energy, charged particles trapped by the Earth's magnetic field within the magnetosphere. The inner belt starts at an altitude of about 800 km and reaches a maximum intensity at about 2000 km. The outer belt reaches a maximum intensity at between three and four Earth radii (18 000–25 000 km). Although commonly referred to as ‘radiation belts’, they contain particles, not radiation. Their presence was predicted by J. A. Van Allen (1914– ).

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