Researchers have been analysing data from the GRAPES-3 muon telescope in Ooty, India, which recorded a massive burst of galactic cosmic rays on 22 June 2015.
For 2 hours, Earth’s magnetosphere was being bombarded by these particles which emit immensely high-energy radiation, and travel through space at nearly the speed of light.
These things are so powerful, they can easily penetrate the hull of a spacecraft, and Earth’s magnetic shield is our first line of defence against them.
About 40 hours before the June 22 event, a giant cloud of plasma was ejected from the Sun’s corona and eventually struck the magnetosphere at speeds of about 2.5 million kilometres per hour.
The giant cloud of plasma triggered a severe geomagnetic storm that was responsible for radio signal blackouts in many high latitude countries in North and South America.
It also resulted in a supercharged aurora borealis – which is created when charged particles from outer space reach Earth’s atmosphere. But now researchers have finally realised the full extent of that relentless bombardment of cosmic rays.
In fact, the team says the bombardment was so relentless, it caused a severe compression of the magnetosphere forcing it to shrink from 11 to 4 times the radius of Earth. The geomagnetic storm was powerful enough to actually ‘reconfigure’ our magnetic shield, prising open weak spots to let radiation and cosmic rays slip through.
“The occurrence of this burst also implies a 2-hour weakening of Earth’s protective magnetic shield during this event,” the researchers report. So the good news is our magnetosphere was only temporarily cracked but the bad news is that it can be cracked at all.
There’s not a whole lot we can do about that, but the researchers hope that by continuing to search for these cracks as they happen – and in past events – we’ll be better prepared to deal with the next time those cosmic rays burst through and wreak havoc.
The research has been published in Physical Review Letters.
Galactic Cosmic Rays
G4 ALERT: ANOTHER STORM REACHES SEVERE LEVELS
Keep in Mind, A Solar Superstorm could Send us Back into the Dark Ages.
ESO, ESA/HUBBLE & NASA
Source: nemesis maturity