Earth’s magnetic field anomaly called an atmospheric “Pothole”


According to USA Today, there is an evolving dent in the Earth’s magnetic field over South America and the southern Atlantic Ocean. ~

Known as the South Atlantic Anomaly (or SAA), SAA is an unusually weak spot in Earth’s magnetic field and is growing and splitting into two lobes. On Earth’s surface, the SAA creates no noticeable harm – but in space, the anomaly is like a “pothole” for satellites and spacecraft. ~

NASA, speaking Monday in a news release, said that “Earth’s magnetic field acts like a protective shield around the planet, repelling and trapping charged particles from the Sun.[But the SAA] allows these particles to dip closer to the surface than normal.” According to NASA, particle radiation may interfere with onboard computers and data collection in space. If a satellite is hit by a high-energy proton, it can lead to temporary or permanent damage — triggering protective shutdowns by operators as they fly through the SAA. Many low-Earth orbit spacecraft, like the International Space Station (ISS), also pass through the SAA. The astronauts inside are not in any danger due to the anomaly, but the SAA can cause occasional – or in the ISS’s case, monthly – “blips,” or short losses, in data collection. ~

The SAA is caused by two features from Earth’s core: the flow of molten metals and the tilt of the magnetic axis. Nasa plans to study the anomaly to better understand how the planet is changing and help create a safer future for in-space instruments. “Even though the SAA is slow-moving, it is going through some change in morphology, so it’s also important that we keep observing it by having continued missions,” Terry Sabaka, a geophysicist at NASA’s Goddard Space Flight Center, said in the Monday statement. “Because that’s what helps us make models and predictions.” ~


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