– Scientists have discovered that a giant plasma cloud ejected from the solar corona, moving with a speed of about 2.5 million kilometers per hour struck our planet, causing a severe compression of Earth’s magnetosphere from 11 to 4 times the radius of Earth.
A coronal mass ejection (or CME) is a giant cloud of solar plasma drenched with magnetic field lines that are blown away from the Sun during strong, long-duration solar flares and filament eruptions.
Earth is enveloped in a protective magnetic envelope called the magnetosphere, extending over a radius of a million kilometers.
It can change shape in response to the Sun’s effects, causing various types of space weather on Earth.
Earth’s magnetic field is our planet’s first line of defense – a shield – against the bombardment of the solar wind. This stream of plasma is launched by the Sun and travels across the Solar System, carrying its own magnetic field with it.
Our magnetosphere is the first line of defense, shielding us from the continuous flow of solar and galactic cosmic rays, thus protecting life on our planet from these high intensity energetic radiations. Without it there would be no life on our planet.
Scientists have previously warned that Earth’s magnetic shielding has been “severely compromised and it may be in danger.
On 22 June 2015, the GRAPES-3 muon telescope, the largest and most sensitive cosmic ray monitor operating on Earth located at TIFR’s Cosmic Ray Laboratory in Ooty recorded a burst of galactic cosmic rays of about 20 GeV lasting for two hours. It triggered a severe geomagnetic storm that generated Aurora Borealis, and radio signal blackouts in many high latitude countries.
Physicists and engineers at the Cosmic Ray Laboratory have conducted multiple simulations and analyzed the effects of the giant plasma cloud hitting out planet. The results show the Earth’s magnetic shield temporarily cracked due to the occurrence of magnetic reconnection, allowing the lower energy galactic cosmic ray particles to enter our atmosphere. Earth’s magnetic field bent these particles about 180 degree, from the day-side to the night-side of the Earth.
This temporary ‘crack’ in the magnetic field, that allowed dangerous galactic cosmic ray particles into our atmosphere.
“The occurrence of this burst also implies a two-hour weakening of Earth’s protective magnetic shield during this event,” the study said. “It indicates a transient weakening of Earth’s magnetic shield.”The research has been published in Physical Review Letters.