Part 3/12:
The South Atlantic Anomaly: A Growing Weak Point
The SAA is a magnetospheric "hole" located above South America and the Atlantic Ocean, where Earth's magnetic field strength is significantly weaker than elsewhere—sometimes halving the typical strength. This weakness allows higher-energy charged particles from the Van Allen belts to dip closer to Earth's surface, creating a zone that can damage satellites and spacecraft passing through it.
Historically, the SAA has been a concern for space agencies, as increased radiation levels can lead to malfunctions in satellites and instruments like the Hubble Space Telescope. Its notoriety peaked with the 2016 failure of Japan’s Hitomi X-ray Observatory, attributed to intense radiation exposure caused by the anomaly.