NASA is monitoring a “huge anomaly” in the Earth’s magnetic field to reveal its mystery

NASA is actively monitoring a strange anomaly in Earth’s magnetic field, as a giant region of low magnetic density extends in the sky above the planet, between South America and southwest Africa. This wide and growing phenomenon called the “South Atlantic Anomaly” has intrigued scientists for years.

NASA satellites and spacecraft are particularly vulnerable to the weak magnetic field strength within the anomaly, and the resulting exposure to charged particles from the sun.

NASA likened the South Atlantic anomaly to a “bending” in the Earth’s magnetic field, or a kind of “crater in space,” which generally does not affect life on Earth, but the same cannot be said about its impact on the orbit of spacecraft, including That’s the International Space Station, which passes directly through the anomaly as it orbits the planet at low altitudes in Earth’s orbit.

During these encounters, the low magnetic field strength within the anomaly means that technological systems aboard satellites can short-circuit and malfunction if they collide with high-energy protons emitted from the sun.

These random strikes would normally result in low-level malfunctions, but they carry the risk of causing significant data loss, or even permanent damage to key components—threats that require satellite operators to routinely shut down spacecraft systems before spacecraft enter an aberration zone.

Mitigating these risks in space is one of the reasons why NASA follows the anomaly puzzle, which represents a great opportunity to investigate a complex and difficult-to-understand phenomenon, and NASA’s vast resources and research groups are uniquely designated to study its occurrence.

“The magnetic field is actually a superposition of fields from many existing sources,” geophysicist Terry Sabaka of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, explained in 2020.

The primary source is a swirling ocean of molten iron within the Earth’s outer core, thousands of kilometers underground. The movement of that mass generates electric currents that create the Earth’s magnetic field, though not necessarily uniformly, it seems.

“The observed anomaly can also be explained as a result of weakening the dominance of the dipole field in the region,” said geophysicist and NASA mathematician Weijia Kuang in 2020.

He explained that, more specifically, the local field with the opposite polarity grows strongly in the anomaly region, which makes the field strength very weak, weaker than that in the surrounding regions.

While many scientists still do not fully understand this anomaly and its implications, new insights are constantly shedding light on this strange phenomenon.

For example, one study led by NASA heliophysicist Ashley Greeley in 2016 revealed that the South Atlantic Anomaly is drifting slowly in a northwesterly direction.

However, he doesn’t just move. More importantly, the phenomenon appears to be in the process of splitting in two, as researchers discovered in 2020 that the anomaly appeared to split into two different cells, each representing a separate center of magnetic minimum within the larger anomaly.

The future of the South Atlantic Anomaly remains unknown, but there is evidence that the anomaly is not a new phenomenon. In this context, a study published in July 2020 indicated that this phenomenon is not a strange event in recent times, but rather a recurring magnetic event that may have affected Earth 11 million years ago.

If so, this could indicate that the South Atlantic Anomaly is not a cause or harbinger of an inverting of the entire planet’s magnetic field, which it does, if not for hundreds of thousands of years at a time.