A small but developing bump in the Earth's magnetic field currently can cause major problems for satellites. The Earth's magnetic field acts like a protective shield around the planet, repelling charged particles from the sun and trapping them. However, over South America and the southern Atlantic, an unusually weak spot allows particles to reach closer to the Earth's surface. Particle radiation in this region can shut down onboard computers and disrupt data collection from satellites that pass through it. This is the main reason why scientistsfrom NASAwant to track and investigate the anomaly.
What does the earth's magnetic field currently look like?
The anomaly, which stretches across the South Atlantic, is also of interest to NASA Earth scientists. There they monitor changes in the magnetic field strength. This is important both in terms of the impact of such changes on the Earth's atmosphere and an indicator of what is happening to the Earth's magnetic fields deep within the Earth. Currently, the strange event is causing no visible impact on daily life on the surface. However, recent observations and forecasts show that the region is spreading westward and continuing to lose intensity. The magnetic field also splits up. Current data shows that the valley of the anomaly, or region of minimum field strength, has split into two lobes. This poses additional challenges for satellite missions. The South Atlantic Anomaly arises from two features of Earth's core: the tilt of its magnetic axis and the flow of molten metals within its outer core.
The forces in the core and the tilt of the magnetic axis combine to create the anomaly, the area of weaker magnetism. This allows charged particles trapped in the Earth's magnetic field to fall closer to the surface. Although the South Atlantic Anomaly arises from processes within the Earth, it has effects that extend far beyond the Earth's surface. The region can be dangerous for low Earth orbit satellites moving through it. So a variety of NASA scientists in geomagnetic and geophysical research groups are observing and modeling this anomaly to monitor and predict future changes. This allows people to prepare for future challenges for satellites and astronauts in space.
Research results
The one in the magazineSpace Weather published resultswere also able to provide a clear picture of the type and amount of particle radiation received as it passed through the anomaly. Therefore, this highlighted the need for continuous monitoring in the region. The team is currently assessing the Earth's magnetic field using data from the European Space Agency's SWARM satellite, previous missions from agencies around the world and ground measurements. The researchers combine the sorted data with their core dynamics model to predict geomagnetic secular variation (rapid changes in the magnetic field) for the future.
Although the anomaly moves slowly, its morphology changes. Therefore, it is also important that scientists continue to monitor them by continuing their missions. The changing magnetic field offers researchers new opportunities to understand the Earth's core. This allows them to take a closer look at its dynamics in relation to other aspects of the Earth system. By tracking this slowly evolving bump in the magnetic field, researchers can better understand how our planet is changing and prepare for a safer future for satellites.
