Aurora dazzles in Ladakh skies after geomagnetic storm hits earth
An aurora dazzled in the skies in India's Ladakh after a severe geomagnetic storm hit Earth. Taking to Twitter, the Indian Institute of Astrophysics (IIA) said last Saturday (April 29) that it captured this phenomenon on a 360-degree camera on April 22-23 night. "This is a time-lapse of the sky taken by a 360 deg camera at from Hanle on 22/23 April night. You can see the aurora lights due to an intense geomagnetic storm that hit the Earth. It is extremely rare to see the aurora at such a low latitude!" the IIA tweeted.
The IIA said that at 11.42 pm on April 21, the sun launched a Coronal Mass Ejection (CME) towards the earth. "This CME (speed of 500-600 km/s) was associated with an M1 class solar flare. The CME arrived at Earth late on April 23 at 10 PM," Wageesh Mishra, a professor at the IIA said.
Mishra said that this geoeffective CME led to an excellent night for auroral activity. He added that the aurora came to "lower-than-usual latitudes" overnight leading to rare sightings from Europe, China and Ladakh in India.
"Such a severe geomagnetic storm last occurred in 2015," the professor pointed out.
What are Coronal Mass Ejections?
According to the US government's Space Weather Prediction Centre, Coronal Mass Ejections, also known as CMEs, are large expulsions of plasma and magnetic field from the Sun’s corona. CMEs can eject billions of tons of coronal material and carry an embedded magnetic field (frozen in flux) that is stronger than the background solar wind Interplanetary Magnetic Field (IMF) strength.
The Space Weather Prediction Centre further says that CMEs travel outward from the Sun at speeds ranging from slower than 250 kilometres per second (km/s) to as fast as nearly 3000 kms.
"The fastest Earth-directed CMEs can reach our planet in as little as 15-18 hours. Slower CMEs can take several days to arrive. They expand in size as they propagate away from the Sun and larger CMEs can reach a size comprising nearly a quarter of the space between Earth and the Sun by the time it reaches our planet," it adds.
