South Atlantic Anomaly:
A giant dent in Earth’s magnetic field, called the South Atlantic Anomaly, is continuing to expand, according to the latest data from a trio of satellites monitoring our world.
- It is a unique location on Earth where the magnetic field is weaker than normal.
- It is southeast of South America and southwest of Africa. In this area, the planet’s magnetic field dips down.
- It was first identified in the 19th century.
- Earth’s magnetic field acts like a protective shield around the planet, repelling and trapping charged particles from the Sun.
- SAA exists because the Earth’s inner Van Allen radiation belt comes closest to the planet’s surface, causing an increased flux of energetic particles.
- This leads to the penetration of solar energetic particles deep into Earth’s atmosphere, posing severe problems for airplanes and ships’ positioning systems as well as spacecraft electronic systems.
- The Van Allen radiation belt is a zone of energetic charged particles, most of which originate from the solar wind.
- The particles are captured by and held around a planet by that planet’s magnetic field.
- It surrounds Earth, containing a nearly impenetrable barrier that prevents the fastest, most energetic electrons from reaching Earth.
- The outer belt is made up of billions of high-energy particles that originate from the Sun and become trapped in Earth’s magnetic field, an area known as the magnetosphere.