Auroras, also known as northern lights in the Northern Hemisphere, occur only near the North or South Pole, and are not seen in India. In April 2023, auroras were seen in India for the first time ever. The Indian Astronomical Observatory located over Mount Saraswati in Hanle, Ladakh, India, captured aurora lights on its camera on the nights of April 22 and 23.
An intense geomagnetic storm that hit Earth on April 21, 2023, resulted in mesmerising auroras in several regions of Earth, including Ladakh.
Bengaluru-based Indian Institute of Astrophysics (IIA), which operates the Indian Astronomical Observatory, said on Twitter that it is “extremely rare” to see auroras at latitudes as low as those of Ladakh. Auroras are seen only in high-latitude regions, near the Arctic and Antarctic circles, which are situated about 66.5 degrees north and south of the equator.
A 360-degree camera belonging to the Indian Astronomical Observatory captured a time-lapse video of the sky on the nights of April 22 and 23. The video shows breathtaking auroras seen over Ladakh.
#Aurora from #Ladakh!
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 aurora at such a low latitude! @dstindia (1/n) pic.twitter.com/gGbrw86vsb
— IIAstrophysics (@IIABengaluru) April 29, 2023
More about geomagnetic storms and auroras
When there is a very efficient exchange of energy from solar winds into the space environment surrounding Earth, a major disturbance occurs in the Earth’s magnetosphere, or the area of space around Earth controlled by the planet’s magnetic field. This disturbance is known as a geomagnetic storm, according to the National Oceanic and Atmospheric Administration (NOAA).
Auroras are a spellbinding display of light in the night sky, and occur as a result of geomagnetic storms.
Solar winds consist of charged particles that travel outward into the solar system. Upon reaching Earth’s magnetic field, solar winds result in an explosive process that allows charged particles from space to accelerate into the planet’s atmosphere, according to NASA. This process is called magnetic reconnection.
Earth’s magnetosphere continuously oscillates as a result of solar winds interacting with it. Solar wind particles become trapped in the long tail of the magnetosphere, and are accelerated towards Earth’s poles when magnetic reconnection occurs.
While the solar wind particles are accelerated into Earth’s atmosphere, they may interact with atoms and molecules in the planet’s upper atmosphere. This increases the energy states of the atoms in Earth’s upper atmosphere. The extra energy is released as a burst of light. A billion individual collisions like this together constitute a glowing aurora.
In this way, auroras illuminate the magnetic field lines of Earth.
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Solar phenomena which caused auroras in Ladakh
The Sun released a coronal mass ejection towards Earth at 18:12 UTC (11:42 pm IST) on April 21, according to the NOAA. The coronal mass ejection was linked with an M1 solar flare.
A coronal mass ejection is a large expulsion of plasma and magnetic field from the Sun’s corona, and travels outward from the Sun at speeds ranging from 250 kilometres per second to 3,000 kilometres per second. Meanwhile, solar flares are flashes of light that occur on the Sun in various wavelengths. When magnetic energy is released from sunspots, intense bursts of radiation, or solar flares occur.
Quoting Wageesh Mishra, an assistant professor at the Indian Institute of Astrophysics, the institute said the coronal mass ejection arrived at Earth at 10 pm IST on April 23.
The coronal mass ejection proved to be an excellent night for auroral activity. The auroras were observed in lower-than-usual latitudes, Mishra was quoted as saying by the Indian Institute of Astrophysics. He also said that the last time such a severe geomagnetic storm occurred was in 2015, and that the event resulted in rare sightings of auroras in Europe, China and Ladakh.
