On Tuesday (August 22), scientists announced they may have found evidence of the most massive star ever seen being torn apart by a black hole, and the giant accused of this crime appears to have literally dumped the insides of its stellar victim into the darkness of the planet. space. .
“We’re looking into the innards of what used to be a star,” said Jon Miller of the University of Michigan, who led a study on the findings. he said in a statement. “The elements that remain are clues we can follow to find out what type of star disappeared.”
Such elementary analysis led the team to believe that the ravaged star once hosted roughly three times the mass of our sun, meaning it is rivaled for its title only by a glowing beast associated with something known as a “Scary Barbie” event reported to early this year. Scary Barbie is the name given to a possible cosmic affair in which a star with a staggering 14 times the mass of our sun was destroyed by a black hole. For context, the mass of the sun is 333,000 times that of Earth, but there is considerable uncertainty surrounding the Scary Barbie event, as you’ll see below.
The recently studied event, dubbed ASASSN-14li, sounds a lot more formal than Scary Barbie. And unlike the Scary Barbie star, there is considerable evidence for the size of the ASASSN-14li object, thanks to new information from the NASA study. Chandra X-ray Observatory and European Space Agency XMM-Newton. However, to be clear, ASASSN-14li was first discovered in 2014.
“Observing the destruction of a massive star by a supermassive black hole is fascinating because more massive stars are expected to be significantly less common than lower-mass stars,” said Enrico Ramírez-Ruiz of the University of California, Santa Cruz, co-author. of the study, he said in the statement.
An illustration of the black hole associated with the studied tidal disturbance event. (Image credit: NASA/CXC/M.Weiss)
“These X-ray telescopes can be used as forensic tools in space,” co-author Brenna Mockler, of the Carnegie Observatories and the University of California, Los Angeles, said in the statement.
Events like ASASSN-14li and Scary Barbie, involving a black hole terrorizing a star, are called tidal disturbance events, or TDEs. According to the press release, when the gravitational forces of a black hole begin to impact an unlucky star that got too close, it sends out a flare that emits optical, ultraviolet, and X-ray wavelengths. This flare occurs in conjunction with the heating of the debris of the star.
The researchers then used their two powerful instruments to study those TDE-based wavelengths and determine the concentrations of elements surrounding the black hole in ASASSN-14li, which lies about 280 million light-years from Earth. In doing so, they analyzed the ratio of nitrogen to carbon present at a cosmic crime scene in startling detail.
And most importantly, that observed ratio seemed to be in line with what would be expected to be found within a star about three times as massive as the Sun, Mockler explained.
From there, the team reasoned that what they have been studying is actually the “guts” of a doomed star with those dimensions, caught in the clutches of a supermassive black hole.
These findings contrast with previous work, published in 2017, which suggested that the star in ASASSN-14li was something like 0.6 times the mass of our sun. In fact, some other studies, the team notes, even suggested that the gas surrounding ASASSN-14li’s black hole wasn’t associated with a single star at all, but rather came from a bunch of eruptions spewed out of the void itself.
“ASASSN-14li is exciting because one of the most difficult things with tidal disturbances is being able to measure the mass of the unfortunate star, as we have done here,” said Ramírez-Ruiz.
The scientists used an X-ray spectrum from Chandra to investigate the elements contained in this wind, including detecting nitrogen. X-ray data indicates that the star in ASASSN-14li was about three times the mass of the Sun, making it one of the largest stars ever destroyed in a TDE. (Image credit: NASA/CXC/Univ of Michigan/J. Miller et al)
But maybe the Scary Barbie star will live up to her feisty name and eventually take the cake for her. Right now, the only evidence we have for this huge stellar object comes from the brightness of its flare, not exactly its chemical composition. Perhaps it is better to live in happiness, assuming that the world in which gigantic black holes tear apart stars of 14 solar masses may not be the world in which we find ourselves.
source: https://iopscience.iop.org/article/10.3847/2041-8213/ace03c