Rare Northern lights witnessed in Ladakh; not an 'air glow', confirms Hanle sources

Aurora borealis or Northern lights which are usually seen in Polar regions were captured in Ladakh, India last month. The colourful “curtains” of dazzling light are actually billions of charged particles moving into space at ultra-high speeds. When they arrive in the direction of Earth, they cause a disturbance in the Earth's magnetic field and enable us to see the aurora lights.

What makes it a once-in-a-lifetime event?
After analysing the aurora, Hanle sources told TOI that it appears to be a “stable auroral red (SAR) arc” —itself a very rare event in Ladakh—and not a conventional aurora. An SAR arc is a band of reddish light seen in the sky. Unlike auroras where various colours appear in moving patterns, SAR displays are static and monochromatic. Both appear during periods of geomagnetic activity triggered by a wave of charged matter blasted out of the Sun, but their mechanism of formation is slightly different.


“Even if it was an SAR arc that appeared in the sky here, it was a once-in-a-lifetime event,” the TOI sources said.

The TOI source at Hanle said instruments at the observatory had ruled out the possibility of the coloured light seen over Ladakh being “air glow”, an unrelated phenomenon invisible to the eye but which often shows up as a region of faint colour in night sky images.

On April 23-24, the Indian Astronomical Observatory above Mount Saraswati captured a rare phenomenon: A geomagnetic storm that struck Earth's magnetic field, causing the charged particles from the sun to collide with atoms and molecules in the Earth's atmosphere. These collisions result in “Aurora” or the northern or southern lights. The regions where the aurora can be seen are Earth’s magnetic poles and regions near them. Moreover, a clear sky would also help in seeing these lights.


The striking of the light particles from the sun with Earth’s magnetic field is a rare phenomenon. But even rarer is it being captured by a camera. Fortunately, the Indian Astronomical Observatory above Mount Saraswati was able to capture it. These waves were witnessed from Europe, China and Ladakh in India. Such a happening was last witnessed in 2015.

(inputs from TOI)