Nasa’s Fermi Gamma-ray Space Telescope recorded the powerful eruption on the surface of the sun on March 7.
The flare produced such an outpouring of gamma rays – a form of light with even greater energy than X-rays – that the sun briefly became the brightest object in the gamma-ray sky.
A solar flare is an explosive blast of light and charged particles.
The powerful March 7 flare, which earned a classification of X5.4 based on the peak intensity of its X-rays, is the strongest eruption so far observed by Fermi’s Large Area Telescope (LAT).
Nicola Omodei, an astrophysicist at Stanford University in California, said: ‘For most of Fermi’s four years in orbit, its LAT saw the sun as a faint, steady gamma-ray source thanks to the impacts of high-speed particles called cosmic rays.