Earth’s magnetic field weakens
Part of: GS-Prelims and GS-I – Geographical phenomenon
- As per the reports, the magnetic field around the earth, on an average, has lost almost 10% of its strength over the last two centuries.
- The magnetic field of the earth protects us from the solar radiation.
- A rapid shrink has been observed in the South Atlantic Anomaly (SAA).
- One most speculated reason behind this is that there is a chance that the time for Earth’s pole reversal is approaching.
- Pole reversal happens when the north and south magnetic poles flip.
- This flip does not occur immediately or suddenly.
- It takes place over centuries and while it is taking place, there would be multiple north and south magnetic poles during this period, all around the planet.
- This is not the first time for the pole reversal to take place.
- These reversals take place roughly every 250,000 years.
- This is not going to affect or alarm the general public.
- However, It is causing technical difficulties for various satellites and spacecrafts.
- As the magnetic field becomes weaker, charged particles from the cosmos can penetrate through to the altitudes at which low-Earth orbiting satellites fly.
Important value additions
South Atlantic Anomaly (SAA)
- SAA is a stretch between Africa and South America.
- It is an area where the Earth’s inner Van Allen radiation belt comes closest to the Earth’s surface.
- The SAA is the near-Earth region where the Earth’s magnetic field is weakest relative to an idealized Earth-centered dipole field.
A Van Allen radiation belt
- It is a zone of energetic charged particles, most of which originate from the solar wind, that are captured by and held around a planet by that planet’s magnetic field.
- Earth has two such belts and sometimes others may be temporarily created.
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