Scientists now know more about a strange cloud that somehow escaped an encounter with a supermassive black hole.
In a recent study, scientists discovered that the cloud—dubbed G2—is actually three new stars that are surrounded by the gas and dust that formed them.
Astronomers discovered G2 in 2011. And when they first noticed the formation, it was on its way towards a black hole named Sgr A*.
As G2 headed towards Sgr A*, scientists assumed that the black hole would rip apart the then-unknown object. And by the end, the hole would swallow the remnants and produce a galactic light show.
In 2014, G2 skimmed the black hole. But instead of being destroyed, it merely elongated as it passed Sgr A*. Then once G2 was far enough away from the dangerous void, it simply returned to its original shape.
The Mysterious Cloud May Answer More Questions about Black Holes
The ability to survive a supermassive black hole wasn’t the only trait of G2 that puzzled researchers. The cloud of dust that surrounds the stars is also much hotter than it should be. At first notice, scientists thought that Sgr A* or other stars were heating the object. But as the cloud moved, the temperature did not change, which meant that G2 was heating itself.
That realization led to the decision that the object had to be a star cluster. And while studying G2, scientists found four more G objects in the Milky Way, which seems like a lot of merged stars.
However, Florian Peißker, an astrophysicist from the University of Cologne in Germany, has been observing similar objects for 14 years. And he’s certain that he’s solved the mystery behind G2. But it’s more exciting than just three ordinary stars.
The stars are only one million years old. That may seem ancient in Earth years, but it’s very young for a star. And scientists have rarely observed stars that new, which is why they didn’t peg the cloud of dust immediately.
“That G2 actually consists of three evolving young stars is sensational,” Peißker said.
Florian Peißker and his team of researchers believe the lone stars once belonged to a larger star system. But Sgr A* affected the system’s gravity and broke the cluster apart.
However, finding answers about G2 only creates more questions for the scientific world. The environment surrounding the black hole should not allow star formation. But they’re forming anyway. So scientists are trying to decide how G2 and the other similar objects came to be.
“The new results provide unique insights into how black holes work,” Peißker added.
“We can use the environment of SgrA* as a blueprint to learn more about the evolution and processes of other galaxies in completely different corners of our Universe.