A Weak Spot in Earth’s Magnetic Field Is Worsening
A weak area in Earth’s magnetic field is expanding, increasing exposure of satellites and astronauts to solar radiation. This finding comes from over a decade of data collected by three orbiting observatories.
South Atlantic Anomaly Growth
The European Space Agency’s Swarm satellite trio has observed that the South Atlantic Anomaly (SAA), a region of weakened magnetic protection over the South Atlantic Ocean, has expanded significantly. Since 2014, this anomaly has grown by an area about half the size of continental Europe.
Changes in Other Magnetic Regions
- The strong magnetic field over Canada has decreased in size.
- Meanwhile, the strong magnetic field region in Siberia has increased.
“The region of weak magnetic field in the South Atlantic has continued to increase in size over the past 11 years since the launch of the Swarm satellite constellation,” explained Chris Finlay, a geomagnetism researcher at Danmarks Tekniske Universitet.
“Although its growth was expected based on early observations, it is important to confirm this change in Earth’s magnetic field is continuing.”
Research and Monitoring
Chris Finlay, lead author of a study published in Physics of the Earth and Planetary Interiors, analyzed data from the Swarm satellites. Launched in 2014, these three satellites continuously monitor magnetic signals originating from Earth's core, mantle, ionosphere, and magnetosphere.
Implications
The expansion of the South Atlantic Anomaly could pose increased risks to satellites and space travelers due to heightened solar radiation exposure in this region.
Summary: The South Atlantic Anomaly’s ongoing growth, confirmed by Swarm satellite data, highlights increasing vulnerability of satellites and astronauts to solar radiation within this expanding weak magnetic zone.