Nagoya University researchers observe high-energy electrons penetrating Earth's radiation barrier

Scientists from Nagoya University have observed high-energy electrons penetrating Earth's radiation barrier, a phenomenon previously thought to be impenetrable. During an analysis of intense magnetic activity on May 1, 2024, researchers detected these particles breaching the boundary of the Van Allen radiation belts.

The Earth's magnetic field typically traps charged particles in two doughnut-shaped regions. While a distinct boundary was identified in 2014 at the inner edge of the outer radiation belt, approximately 19,100 kilometers from Earth's center, these high-energy electrons were found to bypass this limit during a recent geomagnetic storm.

Data from the JAXA Arase probe revealed an immense number of extremely energetic electrons moving at speeds near the speed of light. Some of these particles possess enough energy to penetrate the shielding used in satellites, potentially increasing the risk of damage to orbital technology. The research team, led by Professor Yoshizumi Miyoshi, is investigating whether these particles shifted from the outer belt inward or if there was a sudden energy surge within the existing population.