The brightest gamma-ray burst ever observed hits Earth and excites researchers because such an event occurs only once in 10,000 years.
Baton Rouge - Last fall, Earth was struck by an exceptionally bright and long-lasting pulse of high-energy radiation that caught the attention of astronomers worldwide.
The radiation was the result of a gamma-ray burst, among the most powerful explosions in the solar system.
Such a burst can release as much radiation in a matter of seconds as our sun would in its entire lifetime.
The October 9, 2022 gamma-ray burst was a remarkable event, researchers suspected soon after the burst.
This outburst, complicatedly named GRB 221009A, quickly earned the nickname "BOAT" as an acronym for "brightest of all time."
Further investigation of the sky event confirmed the astronomers' assumptions and showed that the BOAT burst was indeed an extraordinary event.
A gamma-ray burst this bright only happens once every 10,000 years
Eric Burns of Louisiana State University at Baton Rouge said in a statement, "GRB 221009A was probably the brightest X-ray and gamma-ray flare to have occurred since the dawn of human civilization."
The assistant professor of physics and astronomy has analyzed over 7,000 gamma-ray bursts to find out how common such bright bursts are.
The answer is that a comparable eruption only occurs about once every 10,000 years.
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Astronomers suspect that GRB 221009A represents the birth of a new black hole formed at the heart of a collapsing star.
As shown here, the black hole propels powerful jets of particles traveling close to the speed of light.
The rays penetrate the star, emitting X-rays and gamma rays as they stream into space.
(artistic representation)
© NASA/Swift/Cruz de Wilde
In fact, the gamma-ray burst that occurred in October 2022 was so bright that most gamma-ray instruments in space were blinded and unable to record the exact intensity of the radiation directly.
But scientists from the USA, China and Russia have jointly reconstructed and analyzed the outbreak.
The investigations revealed that the gamma-ray burst was 70 times brighter than anything previously observed.
Eric Burns called the eruption "absolutely monstrous" at a press conference and explained that nothing "comparable" had ever been seen.
Various telescopes provide data on the gamma-ray burst
Various data sources were used to analyze the outburst, including the NICER X-ray telescope on the International Space Station (ISS) and data from NASA's old Voyager 1 spacecraft in interstellar space.
A focus issue of
The Astrophysical Journal Letters
publishes several studies on the subject.
It's just an absolutely monstrous outburst.
We've never seen anything remotely comparable.
Eric Burns, Louisiana State University at Baton Rouge
Researchers have calculated that it took the signal from GRB 221009A 1.9 billion years to reach Earth.
It is believed to be the "birth cry" of a black hole, formed when the core of a massive star collapsed under its own gravity.
The newly formed black hole quickly attracts the matter around it and shoots out jets of matter (so-called jets) into space in opposite directions.
The particles in the jets are accelerated to nearly the speed of light, emitting X-rays and gamma rays as they hurtle through space.
Fall 2022 gamma-ray burst: Jet was aimed straight at Earth
In fact, the jets were not unusually powerful, but one of them was aimed directly at Earth, explains Kate Alexander of the University of Arizona in Tucson.
The more frontally you can look at the jet, the brighter it appears.
"Because this burst was so close and so bright, it gave us an unprecedented opportunity to collect observations of afterglow across the electromagnetic spectrum and to test how well our models represent what is actually happening in GRB jets," Alexander continues .
For 25 years, the afterglow models of gamma-ray bursts would have worked very well, Alexander knows.
"But they can't fully explain this jet."
Look into the depths of the universe - This is how "Hubble" sees the universe
Look into the depths of the universe - This is how "Hubble" sees the universe
After the gamma-ray burst, researchers expect a supernova
The researchers involved are also concerned with something else: When a gamma-ray burst like the one in October 2022 occurs, astronomers usually expect a brightening supernova a few weeks later - but so far none have been discovered.
"Given the magnitude of the burst, it is surprising that we cannot say for sure whether there is a supernova or not," explains astrophysicist Andrew Levan of Radboud University in Nijmegen, the Netherlands.
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NASA's Swift space telescope photographed the afterglow of gamma-ray burst GRB 221009A about an hour after the first measurement.
The bright rings are caused by X-rays scattered by otherwise unobservable layers of dust in our galaxy lying in the direction of the burst.
The dark vertical line is an artifact of the imaging system.
© NASA/Swift/A.
Beardmore (University of Leicester)
Both the James Webb Space Telescope and Hubble were used to find the expected supernova.
However, the search has so far been unsuccessful because the supernova may be too faint to be detected by the telescopes.
However, there is also the possibility that the entire star collapsed into the black hole instead of exploding.
In order to further investigate the situation, further observations with the two space telescopes are planned.
Just recently, a research team discovered a gigantic black hole - it has more than 30 billion solar masses.
This article was created with the help of machines and carefully checked by the editor Tanja Banner before publication.
Rubric list image: © NASA/Swift/Cruz deWilde
