Why black holes you can’t study directly, scientists often observe their eating habits to understand what these giants are doing. So what does it mean for a black hole to suddenly stop swallowing gas altogether and then suddenly start again, with hungrier than ever?
That was the puzzle that scientists faced while watching a galaxy Known as 1ES 1927 + 654 over a one-month period in 2018. Although the glittering mess left by a black hole’s eating habits often grows and contracts, this time, scientists saw something unprecedented: near-total attenuation and then a brightness far beyond the previous average galaxy.
“Normally we don’t see variations like this in the accumulation of black holes”, Claudio Ricci, astrophysicist at the Diego Portales University in Chile and lead author of the study, said in a statement from NASA.
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The first clues that something was wrong came from observations made by two large survey programs, which scan the skies for flashes, bumps, and buzzes against stable stars. Those first glances led scientists to recruit some X-ray observatories to get a better idea of what was going on in that patch of heaven.
“It was so strange that at first we thought maybe there was something wrong with the data,” said Ricci. “When we saw that it was real, it was very exciting. But we also had no idea what we were dealing with; no one we spoke to had seen anything like this.”
Ricci and his colleagues were studying what scientists call black hole crown, the astonishing halo of incredibly hot gas above and below the food in the black hole, a gas disk known as an accretion disk. The crown glows with X-rays, and the more “food” a black hole consumes, the brighter the crown becomes.
Generally, the crown of a black hole is periodically illuminated or dimmed, for example 100 times more, depending on the food supply of the black hole. That’s a far cry from what the black hole corona did in this particular galaxy. Over the course of 40 days, scientists managed to see it fade by a factor of 10,000; Then, for over three months, the crown lit up again, up to 20 times more powerful than it had been at the start of the event.
Once the scientists confirmed that the confusing data was real, not an error, they had to figure out what might be causing the strange fluctuation.
Investigators now suspect that the black hole tore apart a passing star, inadvertently dumping the debris at its own expense. power disk. Those debris could have dissipated some of the gases, leaving the black hole briefly hungry before the gas rejoined, leaving the object to resume its feast.
But that scenario isn’t necessarily the correct explanation, according to the researchers. “This data set has many puzzles,” Erin Kara, an astrophysicist at the Massachusetts Institute of Technology and co-author of the new study, said in the same statement. “But that is exciting, because it means that we are learning something new about the universe. We think the star hypothesis is good, but I also think we are going to analyze this event for a long time.”
The research is described in a paper published July 16 in The Astrophysical Journal Letters.
Email Meghan Bartels at [email protected] or follow her on Twitter @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook.
