NASA Explores Earth's Magnetic 'Dent'

Earth’s magnetic field acts like a protective shield around the planet, repelling and trapping charged particles from the Sun. But over South America and the southern Atlantic Ocean, an unusually weak spot in the field – called the South Atlantic Anomaly, or SAA – allows these particles to dip closer to the surface than normal.

Currently, the SAA creates no visible impacts on daily life on the surface. However, recent observations and forecasts show that the region is expanding westward and continuing to weaken in intensity.

The South Atlantic Anomaly is also of interest to NASA’s Earth scientists who monitor the changes in magnetic strength there, both for how such changes affect Earth's atmosphere and as an indicator of what's happening to Earth's magnetic fields, deep inside the globe.

Music: "Now We Wait" by Kamal David Kamruddin [PRS]

Video credit: NASA's Goddard Space Flight Center

Jessica Merzdorf (Telophase): Lead Writer
Mara Johnson-Groh (Wyle Information Systems): Lead Writer
Katie Jepson (USRA): Lead Producer
Weijia Kuang (NASA/GSFC): Lead Scientist
Greg Shirah (NASA/GSFC): Lead Visualizer
Andrew Tangborn (UMBC): Scientist
Terence J. Sabaka (NASA/GSFC): Scientist
Scott Luthcke (NASA/GSFC): Scientist
Mary P. Hrybyk-Keith (TRAX International Corporation): Animator
Bailee DesRocher (USRA): Animator
Katie Jepson (USRA): Narration
Tom Bridgman (GST): Visualizer