Black holes that you can not see and avoid are already among the more sinister phenomena in the cosmos. So it may be disturbing that the supermassive black hole in the middle of the Milky Way seems to be getting hungrier.
Astronomers observing the colossal object called Sagittarius A * found that it had apparently consumed nearby matter at unprecedented speed over the past year.
"We've never seen anything like it in the 24 years we studied the supermassive black hole," said Andrea Ghez, a professor of physics and astronomy at the University of California, Los Angeles, and senior research writer. "It's usually a pretty quiet, weak black hole on a diet, we do not know what's going on at this big party."
In the latest study, the team analyzed more than 13,000 133-hole black hole observations since 2003, collected from the Keck Observatory in Hawaii and the Very Large Telescope at the European Southern Observatory in Chile. The black hole itself is not visible, as it even acts as a one-way trap door for light. However, it is possible to detect gas and dust radiation just outside the "event horizon" as they approach their final destiny.
The team noted on May 13 that the area just before the point of no return was twice as bright as the next brightest observation. They also saw major changes on two other evenings this year, with all three of these changes being unprecedented, according to Ghez.
The team also used a technique called speckle holography to re-analyze older, weaker 24-year observations. They concluded that the level of brightness observed this year was unprecedented in the last quarter century.
"The big question is whether the black hole is entering a new phase … and the rate of gas falling into the black hole drain has been increasing for an extended period of time or whether we have just seen the fireworks of a few unusual gas blocks That fall into it, "said Mark Morris, professor of physics and astronomy at UCLA and co-senior author of the newspaper.
One hypothesis is that the Fressrausch is related to the closest approach to the black hole of a star called S0-2 in the summer of 2018, and that a large amount of stellar gas could have reached Sagittarius A * this year.
Another possibility is a bizarre object called G2, most likely two binary stars that approached the black hole in 2014. The black hole might have scraped off the outer layer of G2, Ghez said. This could help explain the increased brightness right in front of the black hole. A third suggestion is that several large asteroids were dragged into the cosmic sinkhole.
The black hole is approximately 26,000 light-years from Earth and poses no threat to our planet. The results appear in Astrophysical Journal Letters.