The South Atlantic Anomaly through the eyes of HEPD-02

A unique perspective on our planet comes from HEPD-02 aboard the CSES-02 mission: at an altitude of 500 km, the instrument records the signatures left by particles, orbit after orbit. Each region has its own “fingerprint”, from the quiet of the equatorial belt, to the South Atlantic Anomaly, where events multiply up to millions per second.

The South Atlantic Anomaly (SAA) is a vast area between South America and southern Africa where Earth’s magnetic field is significantly weaker than the global average. A true “gap” in the magnetic shield, allowing charged solar particles to penetrate closer to the Earth’s surface, generating possible risks for satellites and disrupting radio communications.

The most recent observations indicate that the South Atlantic Anomaly is continuously evolving: it is expanding and may fragment into multiple distinct regions. Monitoring its evolution is crucial for understanding changes in Earth’s magnetic field and for the safety of space technologies. In this context, missions such as CSES-02 and instruments like HEPD-02 represent a fundamental asset, providing continuous, high-precision data on one of the most dynamic and significant phenomena in near-Earth space.

Orbit after orbit, at an altitude of 500 km, HEPD-02 records the signatures left by particles: highlighted is the South Atlantic Anomaly between South America and southern Africa, where events multiply up to millions per second. Credits: Limadou Team