GRB 221009A, also known as Swift J1913.1+1946, was an extraordinarily bright and long-lasting gamma-ray burst (GRB) jointly discovered by the Neil Gehrels Swift Observatory and the Fermi Gamma-ray Space Telescope on October 9, 2022. The gamma-ray burst was around seven minutes long, but was detectable for more than ten hours following initial detection. Despite being around two billion light-years away, it was powerful enough to affect Earth's atmosphere, having the strongest effect ever recorded by a gamma-ray burst on the planet. The peak luminosity of GRB 221009A was measured by Konus-Wind to be ~ 2.1 × 1047 W and by Fermi Gamma-ray Burst Monitor to be ~ 1.0 × 1047 W over its 1.024s interval. A burst as energetic and as close to Earth as 221009A is thought to be a once-in-10,000-year event. It was the brightest and most energetic gamma-ray burst ever recorded, with some dubbing it the BOAT, or Brightest Of All Time.
Near-simultaneous observations were made of GRB221009A from Gemini South in Chile. The image is a combination of 4 exposures in I, J, H, K with two instruments taken in the morning of Friday, October 14, 2022.
Swift's X-ray image of GRB 221009A shows circular rings around the gamma-ray burst. Dust in the Milky Way scattered the x-ray emission of the gamma-ray burst, creating the rings.
In gamma-ray astronomy, gamma-ray bursts (GRBs) are immensely energetic explosions that have been observed in distant galaxies, described by NASA as "the most powerful class of explosions in the universe". They are the most energetic and luminous electromagnetic events since the Big Bang. Bursts can last from ten milliseconds to several hours. After an initial flash of gamma rays, a longer-lived "afterglow" is usually emitted at longer wavelengths.
Artist's illustration showing the life of a massive star as nuclear fusion converts lighter elements into heavier ones. When fusion no longer generates enough pressure to counteract gravity, the star rapidly collapses to form a black hole. Theoretically, energy may be released during the collapse along the axis of rotation to form a GRB.
Positions on the sky of all gamma-ray bursts detected during the BATSE mission. The distribution is isotropic, with no concentration towards the plane of the Milky Way, which runs horizontally through the center of the image.
The Italian–Dutch satellite BeppoSAX, launched in April 1996, provided the first accurate positions of gamma-ray bursts, allowing follow-up observations and identification of the sources.
NASA's Swift Spacecraft launched in November 2004
