Earth  Sun  ID: 13688

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. It is also splitting – recent data shows the anomaly’s valley, or region of minimum field strength, has split into two lobes, creating additional challenges for satellite missions.

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.

Source Material


Lead Writers:
Jessica Merzdorf (Telophase)
Mara Johnson-Groh (Wyle Information Systems)

Lead Producer:
Katie Jepson (USRA)

Lead Scientist:
Weijia Kuang (NASA/GSFC)

Lead Visualizer:
Greg Shirah (NASA/GSFC)

Andrew Tangborn (UMBC)
Terence J. Sabaka (NASA/GSFC)
Scott Luthcke (NASA/GSFC)

Mary P. Hrybyk-Keith (TRAX International)
Bailee DesRocher (USRA)
Walt Feimer (KBR Wyle Services, LLC)

Katie Jepson (USRA)

Tom Bridgman (Global Science and Technology, Inc.)

Please give credit for this item to:
NASA's Goddard Space Flight Center

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DLESE >> Geology
DLESE >> Geophysics
SVS >> Magnetosphere
GCMD >> Earth Science >> Solid Earth >> Geomagnetism >> Magnetic Anomalies
GCMD >> Location >> Van Allen Radiation Belts
SVS >> Geology
NASA Science >> Earth
NASA Science >> Sun

GCMD keywords can be found on the Internet with the following citation: Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version