South Atlantic Anomaly (SAA)

The South Atlantic Anomaly (SAA) is a region over Brazil and the South Atlantic where Earth's magnetic field is weakest, causing the inner Van Allen radiation belt to dip to unusually low altitudes (200 km). LEO satellites passing through the SAA experience significantly elevated radiation exposure, which can cause single-event upsets (SEUs) in electronics, increased sensor noise, and accelerated component degradation. The Hubble Space Telescope suspends observations when passing through the SAA, and the ISS has additional shielding for crew modules in this region.