Astronomers have witnessed the brightest flash of light ever seen, which occurred 2.4 billion light years away from Earth and was most likely caused by the formation of a black hole. Orbiting telescopes detected a burst of gamma-rays, the most intense form of electromagnetic radiation, and its afterglow is still being monitored by scientists around the world.
According to AFP, gamma-ray bursts that last hundreds of seconds, like the one on Sunday, are thought to be caused by dying massive stars 30 times the size of our Sun.
The star explodes as a supernova, then collapses into a black hole, after which matter forms in a disk around the black hole, falls inside, and is spewed out in an energy jet that travels at 99.99 percent the speed of light. The flash emitted photons with a record 18 teraelectronvolts of energy (that’s 18 with 12 zeros behind it), disrupting long-wave radio communications in the Earth’s ionosphere.
“It’s really breaking records, both in terms of the number of photons and the energy of the photons that are reaching us,” said O’Connor, who took new observations early Friday using infrared instruments on the Gemini South telescope in Chile. “Something this bright, this close is truly a once-in-a-lifetime event,” he added.
Gamma-ray bursts in general release the same amount of energy that our Sun produces over its entire lifetime in the span of a few seconds—and this event is the brightest gamma ray burst.
O’Connor
Gamma-ray research first began in the 1960s when US satellites designed to detect whether the Soviet Union was detonating bombs in space ending up finding such bursts originating from outside the Milky Way.
“Gamma-ray bursts in general release the same amount of energy that our Sun produces over its entire lifetime in the span of a few seconds—and this event is the brightest gamma-ray burst,” said O’Connor.
This gamma-ray burst, known as GRB 221009A, was first spotted by telescopes including NASA’s Fermi Gamma-ray Space Telescope, Neil Gehrels Swift Observatory, and Wind spacecraft on Sunday morning Eastern time.
1.9 billion-year-old movie
It originated from the direction of the constellation Sagitta, and traveled an estimated 1.9 billion years to reach Earth—less than the current distance of its starting point, because the universe is expanding.
Observing the event now is like watching a 1.9 billion-year-old recording of those events unfold before us, giving astronomers a rare opportunity to glean new insights into things like black hole formation.
“That’s what makes this sort of science so addictive—you get this adrenaline rush when these things happen,” said O’Connor, who is affiliated with the University of Maryland and George Washington University.
Over the coming weeks, he and others will continue watching for the signatures of supernovas at optical and infrared wavelengths, to confirm that their hypothesis about the origins of the flash are correct and that the event conforms to known physics.
Unfortunately, while the initial burst was visible to amateur astronomers, it has since faded from sight. Supernova explosions are also thought to be responsible for the production of heavy elements such as gold, platinum, and uranium, and astronomers will be looking for their signatures.
Astrophysicists have previously stated that the sheer power of gamma-ray bursts could result in extinction-level events on Earth. However, O’Connor pointed out that because the jets of energy are so tightly focused and are unlikely to occur in our galaxy, we shouldn’t be too concerned about this scenario.
