Earth's magnetic dent splits; creates challenges for satellite missions

The South Atlantic Anomaly can be hazardous for low-Earth orbit satellites that pass through it. For instance, if a key component of the satellite is hit by a high-energy proton, it can cause its function to glitch temporarily or can cause permanent damage.

Researchers at the National Aeronautics and Space Administration (NASA) have tracked an evolving and splitting dent in Earth’s magnetic field that acts as a protective shield around the planet, repelling and trapping charged particles from the Sun.

According to the recent observations and forecasts, the magnetic field over South America and the southern Atlantic Ocean termed as South Atlantic Anomaly (SAA) is not only expanding westward but also splitting into two lobes. As of now, the SAA hasn't created any visible impacts on daily life on the surface, but particle radiation in this region can knock out onboard computers and interfere with the data collection of satellites travel through it, thereby create additional challenges for satellite missions. 

Earth’s magnetic field acts like a protective shield around the planet — but it has an unusually weak spot, where particle radiation can interfere with onboard computers and satellites. How @NASAEarth researchers monitor its changes: https://t.co/kxau4LOaV7 pic.twitter.com/0il8BHz18S

— NASA (@NASA) August 17, 2020

Commenting on the developments, Weijia Kuang, a geophysicist, and mathematician in Goddard’s Geodesy and Geophysics Laboratory said, “The observed SAA can be also interpreted as a consequence of weakening dominance of the dipole field in the region. More specifically, a localized field with reversed polarity grows strongly in the SAA region, thus making the field intensity very weak, weaker than that of the surrounding regions.”

The South Atlantic Anomaly can be hazardous for low-Earth orbit satellites passing through it, a bit like a pothole in a road. For instance, if a key component of the satellite is hit by a high-energy proton, it can cause its function to glitch temporarily or can cause permanent damage. To protect these satellites, operators usually shut down non-essential components when they pass through the SAA. The seriousness of the situation has prompted researchers at NASA and other space agencies to keep observing the changes and prepare for future threats to satellites and the onboard instruments.

By monitoring the dent in the magnetic field and using computer models to study how it might move and change, satellite operators at @NASA and other space agencies can keep their hardware safe. pic.twitter.com/doEppzQGIK

— NASA Earth (@NASAEarth) August 17, 2020

"The changing SAA provides researchers new opportunities to understand Earth’s core, and how its dynamics influence other aspects of the Earth system. By tracking this slowly evolving “dent” in the magnetic field, researchers can better understand the way our planet is changing and help prepare for a safer future for satellites," Kuang further added.