The earth’s magnetic shield is responsible for protecting us against meteorites and charged particles and offering radiation shielding capabilities. It is also responsible for the stunning Northern Lights. But you don’t think about this everyday do you? After all, it’s one of those things that we simply take for granted. But as it turns out, a temporary crack has developed in the earth’s magnetic shield, which is allowing damaging cosmic ray particles to enter the earth’s atmosphere.
What is Magnetic Reconnection?
We don’t see magnetic reconnection on earth. The plasma that makes up 99% of the universe contains magnetic fields which affect the way charged particles in its vicinity move. Usually, the magnetic fields inside these plasmas don’t merge with others or break pattern. However, there are times when the entire pattern changes to something new as these field lines get close to one another. Magnetic reconnection simply taps into the energy stored in the magnetic field and transforms it into kinetic and heat energy, sending particles all along the field lines. Sounds simple enough, but the amount of energy released can actually be devastating. It is this energy that could be responsible for causing UV radiation as well as widespread blackouts.
The Burst That Was
A GRAPES-3 muon telescope in India recorded a burst of cosmic rays that lasted for 2 hours. The fact that the burst happened in all 9 directions suggests that the origin was close to our planet. This also shows the weakening of the planet’s magnetic shield and could hold clues about future storms that have the potential to cripple technological infrastructure here and damage the shield’s radiation shielding capabilities. The burst took place when a cloud of plasma struck earth at a speed of 2.5 million kms/ hr. It caused a compression in the magnetosphere, reducing it from 11 times to 4 times the radius of the planet.
Solar Winds and their Role
The sun’s atmosphere is also made up of plasma, where negative and positively charged particles are separated at immense temperatures. These particles streams out from the corona, filling solar wind in the solar system. However, the sun’s control reduces as the plasma travels further away. Think of this as a squirt gun spraying water. The initial sprays are smooth, but it slowly begins to break into droplets and eventually into a mist.
A Flip in the Poles
Geomagnetic storms are becoming more and more disruptive due to our increasing dependence on technical systems that can be affected by electrical currents. The planet’s magnetic shield has already weakened by as much as 15% within the last 200 years, and this could mean that the poles are about to flip. Some experts believe that a flip is long overdue, but when this occurs, is anybody’s guess. And once that happens, the planet would get exposed to solar winds which could punch a hole in the ozone layer, destroying existing radiation shielding capabilities, knocking out power grids, devastating earth as we know it forever.