In the 1930s, physicist and engineer Karl Jansky detected a continuous source of radio waves when he pointed his radio antenna at the center of our galaxy. After some analysis, scientists realized that these radio waves were emitted by something much farther away than our planet. Sun – but oddly enough, they were comparable in energy to the waves we get from the sun.
With this information, they began to suspect that something truly powerful was lurking at the center of the hub. Milky Way.
Astronomers later realized that the source of these mysterious radio waves was nothing else. supermassive black hole A million times larger than our own sun We call it now Spring A*. The massive object, commonly abbreviated as Sgr A*, basically acts as a gravitational anchor for the entire Milky Way. Since these initial observations, astronomers have come to learn a great deal about Sgr A*; Because astronomers can actually observe it, the black hole offers us our best chance to answer an intriguing question: is star formation possible around it? black holes?
Relating to: Rotating gas helps scientists determine mass of Milky Way’s supermassive black hole
Sgr A* is surrounded by a group of molecular clouds of interstellar hazes where you can see a star or two emerging. However, astronomers reasoned that the proximity of these clouds to the black hole could disrupt possible stellar nurseries operating inside, as extreme tidal and electromagnetic forces are believed to destabilize pockets of gas that often accumulate to form. stars.
“Combination of low intensity moderate and strong tidal forces [supermassive black hole] It makes it difficult for stars to form in the ‘standard’ way, that is, from the collapse of dense clouds of gas. “They break apart before they collapse,” astrophysicist Rosalba Perna of Stony Brook University in New York told Space.com.
More recent observationsbut we pointed out the possibility that star formation may have occurred much closer to Sgr A* than we initially realised.
For some astronomers timeThey observe stars in the vicinity of Sgr A*, but explain that their presence is probably due to their migration towards the black hole after initially forming as distant clusters. But the problem with this explanation is that many of these newly discovered stars appear to be too young to travel far. space To achieve Sgr A*.
Young Stars Spotted Close to Sgr A*
A team of astronomers led by Florian Peißker, a postdoctoral researcher at the Institute of Astrophysics at the University of Cologne, identified the young stellar object X3a.
“It turns out that a few light-years away from the black hole, there is a region that provides the necessary conditions for star formation. This region, a ring of gas and dust, is cold enough and protected against destructive radiation,” Peißker said. explained In a statement.
Surrounding Sgr A* and other supermassive black holes is an accretion disk of gas and dust that falls towards the black hole due to its immense gravity. The special disc surrounding Sgr A* extends from 5 to 30 light years from event horizon of the black hole.
The team believes that X3a may have formed in a gaseous envelope in the outer ring of the accretion disk surrounding Sgr A*. These gas clouds can grow large enough to collapse in on themselves and form protostars.
Researchers have also speculated about other possible explanations for the existence of stars close to Sgr A*.
“The presence of young stars around black holes has caused astrophysicists to broaden their perspectives on star formation, and various theories have been developed to explain them, such as formation in a disk resulting from the disruption of a molecular cloud, followed by formation in a distant cluster. Perna suggests that involution is triggered by a tidal disruption event.” with proper migration and shock compression,” he says.
Perna recently wrote an article This suggested that tidal disruption events (TDEs) close to black holes could create the right conditions for stars to form. TDEs are events in which gravitational instabilities can be introduced into the black hole’s accretion disk; An example of this would be a star falling towards a black hole. These TDEs can interact with a black hole’s accretion disk to produce high densities of gas and twilight, allowing dense clusters to transform into young stars.
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Perna explains that star formation around black holes is likely influenced by the stage of evolution of the black hole in question. When a black hole is “active,” it is surrounded by a vast accretion disk of gas and dust, probably in its early stages when the galaxy surrounding it is a chaotic place. This accretion disk may be a fertile ground for star formation due to the accumulation of high density of material. But now that the Milky Way is much older, things have calmed down and star formation around Sgr A* has probably slowed down compared to what it was in the distant past.
While black holes remain in the category of cosmological mystery, astronomers are learning more about how they interact with their environment to give birth to new stars and influence the evolution of their own galaxies.