Quasar black hole6/17/2023 ![]() It hosts a black hole twice as large as the other quasar known from the same era. Pōniuāʻena is only the second quasar yet detected at a distance calculated at a cosmological redshift greater than 7.5, or 13 billion light-years from Earth. Keck Observatory and Gemini Observatory on Mauna Kea, in Hawaii, confirming its existence and identity. In 2019, the researchers observed the object using the W. The team first detected Pōniuāʻena as a possible quasar after combing through large area surveys. By systematically searching for these rare objects in wide-area sky surveys, astronomers discovered the most distant quasar (named J1342+0928) in 2018 and now the second-most distant, Pōniuāʻena (or J1007+2115). Since the discovery of the first quasar, astronomers have been keen to determine when they first appeared in our cosmic history. “They are the most luminous objects in the Universe,” Hennawi said, “outshining their host galaxies by factors of more than a hundred.” Matter spiraling onto a supermassive black hole generates tremendous amounts of heat making it glow at ultraviolet and optical wavelengths. Quasars are incredibly bright sources of radiation that lie at the centers of distant massive galaxies. It is the first quasar to receive an indigenous Hawaiian name. The researchers have named the object Pōniuāʻena, which means “unseen spinning source of creation, surrounded with brilliance” in the Hawaiian language. The results are currently in preprint on ArXiv and will appear in The Astrophysical Journal Letters. UC Santa Barbara’s Joe Hennawi, a professor in the Department of Physics, and former postdoctoral scholars Frederick Davies and Feige Wang, provided crucial modeling and data analysis tools that enabled this discovery. Now scientists have announced the discovery of the second-most distant quasar ever found, at more than 13 billion light-years from Earth. With a total energy equivalent to 100 supernovas, “it is one of the most luminous transients ever discovered.Often described as cosmic lighthouses, quasars are luminous beacons that can be observed at the outskirts of the Universe, providing a rich topic of study for astronomers and cosmologists. “AT2021lwx is an extraordinary event that does not fit into any common class of transient,” Wiseman said in an email to the Times. The total energy released by AT2021lwx is far greater. The brightest explosion on record is a gamma ray burst known as GRB 221009A, but that outburst was was over in a fraction of the time. “AT2021lwx is a highly energetic event, arguably the most luminous optical transient ever observed,” the team wrote. ![]() At its brightest, the team concludes, the explosion was 2 trillion times as bright as the sun. As material is consumed, shock waves blast through the remnants and the gas swirling around the black hole in an accretion disk. “For something to be bright for two-plus years was immediately very unusual.”Īs it turns out, the best explanation is a dormant black hole up to a billion times more massive than the Sun feasting on a huge cloud of gas. “Most supernovae and tidal disruption events only last for a couple of months before fading away,” Philip Wiseman, an astrophysicist at the University of Southampton and lead author of a paper in the Monthly Notices of the Royal Astronomical Society, told The New York Times. Maybe it was a black hole, gulping down a passing star in a tidal disruption event? Or a flaring quasar. The detonation resembled the sudden flare of a supernova blast, but it didn’t stop and fade away like an exploding star. And it was still going on, dimming much more slowly than might be expected. Looking back through archived data collected by the Asteroid Terrestrial impact Last Alert System, or ATLAS, they found the blast had actually been detected a year earlier. The object, eight billion light years from Earth, is known as AT2021lwx. That’s what a team of astronomers led by researchers at the University of Southampton has found in a brilliant outburst first detected in the constellation Vulpecula in 2020 by the Zwicky Transient Facility in California. Now imagine setting off a firework that explodes and then keeps on exploding. It explodes with a flash and a bang and then it’s over. An artist’s impression of a supermassive black hole pulling in nearby material and heating it to enormous temperatures.
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