The South Atlantic Anomaly makes a section of the southern aurora weaker and likely dimmer.
© Skyimages via Getty ImagesAurora seen above Queenstown, New Zealand. Researchers have discovered a huge dent in Earth's magnetic field weakens the southern lights.
A bizarre dent
in Earth's magnetic field
above the southern Atlantic Ocean weakens the southern lights, new research finds.
The South Atlantic Anomaly
is a large, oval-shaped region over South America and the southern Atlantic Ocean where Earth's magnetic field is weakest. The anomaly is already well known for allowing charged particles from the sun to dip close to Earth's surface, exposing satellites orbiting above to high levels of ionizing radiation, according to NASA
Now, a study published Feb. 8 in the journal Geophysical Research Letters
finds that this weak region also affects the southern aurora, the glowing lights in the upper atmosphere that can be seen at high latitudes. The southern lights occur over and around Antarctica and are the equivalent of the northern lights that dance over the Arctic and Subarctic.
Auroras are caused by solar particles interacting with gas molecules in Earth's atmosphere and are usually considered largely under the control of the sun, said Zhi-Yang Liu
, first author of the study and a researcher at the Institute of Space Physics and Applied Technology at Peking University in China. But the new research highlights the two-way nature of the relationship, Liu told Live Science in an email.