Aditya-L1 images reveal solar flare 'kernel', provide insights into Sun's explosive activity

New Delhi: Images from ISRO's Aditya-L1 -- India's first mission to the Sun -- reveal a solar flare 'kernel' in the lower layers of the atmosphere, providing new insights into the star's explosive activities, according to an analysis.

Seen as bright areas on the Sun, solar flares are giant explosions sending energy, light and high-speed particles into space, thereby impacting space weather and potentially disrupting radio communications and satellite operations.

Researchers from the Inter-University Centre for Astronomy and Astrophysics (IUCAA) in Pune said that on February 22, 2024, the Solar Ultraviolet Imaging Telescope (SUIT) instrument on-board Aditya-L1 captured an image of the X6.3-class solar flare, one of the most intense kind of solar eruptions.

Lead scientist Durgesh Tripathi, senior professor at IUCAA and principal investigator of SUIT, said the observations, captured in unprecedented detail, unveiled secrets hidden in the near ultraviolet wavelength for the first time.

"The solar flare was a powerful reminder of the Sun's dynamic nature," Soumya Roy, a PhD student at the IUCAA and lead author of the analysis published in The Astrophysical Journal Letters, said.

"The bright kernels we detected suggest a previously unseen response of the lower solar atmosphere, offering new insights into flare dynamics," Roy said.

The IUCAA was involved in designing the SUIT in collaboration with institutes, including the Indian Space Research Organisation (ISRO).

The Aditya-L1 mission was launched by the ISRO on September 2, 2023, and successfully injected into a halo orbit around the first Lagrange point 'L1'.

Lagrange points of the Sun are locations in space where the gravitational pull of the Sun and that of other bodies cancel out each other.

At the L1 location, the SUIT observes the Sun 24x7, without any interruption, according to the IUCAA.

In the paper, the authors explained that solar flares are regularly observed using X-ray light.

However, detections of solar flares using ultraviolet light, especially in the near to mid-range, are sparse, they added.

"The results obtained in this (research) letter demonstrate the capabilities of SUIT in flare observations and will help us understand the emission observed in near-ultraviolet," the authors wrote.

The study also highlights how complex physical processes are involved as mass and energy is transferred across layers in the solar atmosphere, the team said.

Solar storms, which include solar flares, are known to occur periodically as the Sun's internal dynamo process -- which creates its magnetic field -- intensifies and weakens.

A cycle of solar activity typically lasts 11 years. The Sun is currently said to be in Solar Cycle 25.

Space agencies and organisations, such as the National Oceanic and Atmospheric Administration (NOAA), US, routinely monitor space weather to provide timely information of disruptions due to solar activity, that can possibly cause communication blackouts and satellite outages.