Member-only story
What is the Magnetic Field and the South Atlantic Anomaly
Magnetic field anomaly grows over Brazil that concerns scientists.
The South Atlantic Anomaly (SAA) is an area where Earth’s inner Van Allen radiation belt comes closest to Earth’s surface, dipping down to an altitude of 200 kilometers (120 mi).
It’s an exceptionally weak spot in the field is called the South Atlantic Anomaly or SAA.
The shape of the SAA changes over time.
This leads to an increased flux of energetic particles in this region and exposes orbiting satellites to higher-than-usual levels of radiation.
The Earth’s magnetic field acts as a protective shield around the planet, repelling and trapping the Sun’s charged particles.
But what happens deep inside Earth does not always stay deep inside Earth.
Energetic, charged particles from the sun get trapped in Earth’s magnetic field, forming the Van Allen radiation belts.
The SAA is the near-Earth region where Earth’s magnetic field is weakest compared to an idealized Earth-centered dipole field.
Since 1972 there is evidence that this anomaly has been growing in size and strength.
