Almost every 114 days, almost like clockwork, a galaxy 570 million light-years away lights up like a fireworks display. Since at least 2014, our viewers have recorded this bizarre behavior; now, astronomers have put the pieces together to find out why.
In the center of the constellation, called ESO 253-G003, a supernatural black hole is torn by a star which, every 114 days, moves close enough to slip some of its material, causing a brilliant flame of transverse light. multi-wave. He then moves away, surviving to be reduced again on the next close approach.
Because of the regularity of the flames, astronauts have nicknamed them “Old Faithful”, like the geyser in Yellowstone National Park.
“These are the most likely and most frequent multi-wave flames we have seen from the heart of the galaxy, and they provide us with a unique opportunity to study this extragalactic Old Faithful in detail,” said the first author of the study, astronaut Anna Payne from the University of Hawai’i at Mānoa.
“We think a supermassive black hole at the center of the galaxy is creating the explosions because it’s partly eating an orbiting giant star.”
The flames were first detected in November 2014, built by the All-Sky Automated Survey for Supernovae (ASAS-SN). At the time, astronomers considered illumination in ESO 253-G003 to be a supernova.
But in 2020, when Payne was looking over ASAS-SN data on ESO 253-G003, she discovered another flame from the same spot. And another man. And another man.
In total, she identified 17 flames, circled about 114 days apart. She and her team then predicted that the galaxy would light up again on May 17, September 7 and December 26, 2020 – and they were right.
They renamed the ever-growing ASASSN-14ko, and these accurate predictions meant they were able to take new, more detailed views of the May flame with a powerful TESS telescope. at NASA. Comments from other previous instruments provided data over a range of waves.
“TESS gave a very detailed picture of that particular flame, but because of the way the mission paints a picture of the skies, it can’t see all of them,” said astronaut Patrick Vallely of State University Ohio. “ASAS-SN collects less information about individual accidents, but provides a longer baseline, which was crucial in this case. The two studies are complementary.”
But a supernova lights up just once, then disappears, as an event like this destroys the original star; so anything else had to cause a light explosion in optical, ultraviolet and X-ray waves.
A truly intriguing black hole that emits regular flames is unheard of while catching an orbiting star – one was identified last year, on a nine-hour blowing plate – but no the case was as simple as ESO 253-G003.
That’s because ESO 253-G003 actually has two galaxies in the final stages of union, which means that there should be two black holes in the middle.
Recent research has shown that two interactive black holes can cause a transition, but the objects in the middle of ESO 253-G003 are thought to be too far apart to interact in this way.
Another ability built was a star banging through a collection disk of material going around and feeding into one of the black holes. This also had to be denied. As the star fell through the disc at different locations and angles, the shapes of the flames should have been different – but the observations showed that the flames from ESO 253-G003 matched closely.
The third capability was again a partial marine disturbance, where a larger object again strikes material from a smaller one.
If a star were in a 114-day eccentric orbit around the black hole, its close approach, or periastron, could be seen looking close enough for material to be removed before it goes gone again.
When this material hits the collection disc, it causes a flame. And this is what seems to be happening.
With this situation in mind, the team analyzed the comments. They analyzed the light curve of each flame, and compared it to other known black hole tidal disturbance events. And they concluded that the star appeared to be orbiting a massive black hole colliding at 78 million solar supplies.
By all means, the star would lose about 0.3 percent of the sun’s mass – about three Jupiters – to the black hole enough to watch the seen flames while allowing the star to live.
“If a large star with a puffy envelope closes, but not too close to a very long orbit, the black hole can steal some of the outer material without tearing out the entire star.” said astronaut Benjamin Shappee of the University of Hawaii Astronomy Institute. “In that case, the big star will just keep coming back and forth until the star is tired.”
It is not clear how long the star and the black hole have sustained this dance, which makes it difficult to work out how long the star has left. But the team has predicted when the next two flames are expected to take place – in April and August this year – and plans to take even more ideas.
It represents a very rare opportunity to understand a large collection of black holes.
“In general, we really want to understand the properties of these black holes and how they grow,” said astronaut Kris Stanek of Ohio State University. “The ability to directly predict the timing of the next program allows us to take data that we could not otherwise have taken, and we are already taking such data. “
The research was presented at the 237th meeting of the Astronomical Society of America. It will also be submitted The Astrophysical Journal, and is available on arXiv.