Growing weak spot in Earth's magnetic field puts astronauts at risk

A weak spot in Earth’s magnetic field known as the South Atlantic Anomaly (SAA) is expanding and intensifying, posing increased risks to satellites and astronauts. Data collected over the past decade by the European Space Agency’s Swarm satellite constellation reveals that since 2014, the SAA has grown by an area roughly half the size of continental Europe and has weakened by 336 nanoteslas. This region’s magnetic field is less able to shield against harmful solar radiation, exposing satellites and crew aboard the International Space Station to higher levels of charged particles that can disrupt electronics and pose health risks. The changes in Earth’s magnetic field are linked to complex processes in the planet’s molten iron core and the shifting of the northern magnetic pole toward Siberia. While the SAA weakens and expands over the South Atlantic, a strong magnetic region over Siberia has grown both in size and intensity, increasing by 0.42 percent of Earth’s surface area and gaining 260 nanoteslas in strength