The magnetic field of our planet acts as a kind of protective shield, responsible for repelling and trapping charged particles released by the Sun. But in the region over South America and the southern part of the Atlantic Ocean, an unusually weak point in this field, Called the South Atlantic Anomaly (SAA), it allows these particles to get closer to the Earth’s surface than normal.

SAA is caused by two natural processes inside the Earth: the tilt of its magnetic axis and the flow of molten metals within its outer core, NASA detailed. Its effects, however, go far beyond the surface of our planet.

Currently, SAA does not directly affect people’s lives. However, this depression in Earth’s magnetic field allows radiation from solar particles to knock out computers onboard spacecraft, as well as interfere with data collection from satellites.

“The region can be hazardous for low-Earth orbit satellites that travel through it. If a satellite is hit by a high-energy proton, it can short-circuit and cause an event called single event upset or SEU. This can cause the satellite’s function to glitch temporarily or can cause permanent damage if a key component is hit,” the space agency explained.

To avoid the loss of instruments or even an entire satellite, it is not uncommon for its non-essential components to be shut down during the time it takes to pass through the SAA.

Investigating and monitoring the anomaly allows NASA scientists to understand how these changes affect Earth’s atmosphere. The SAA also serves as an indicator of what is happening to the magnetic fields of our planet, in the depths of the globe. By monitoring this anomaly, researchers can better understand how our planet is changing, and thereby find solutions for a safer future for satellites.