What’s New
Astronomers have observed a binary star system orbiting near the supermassive black hole at the center of the Milky Way galaxy.
The discovery of Sagittarius A* (Sgr A*), published Tuesday in Nature Communications, is the first confirmed instance of two stars gravitationally bound to each other so close to a black hole.
Why It Matters
The environment surrounding supermassive black holes like Sgr A*––which is 4 million times the mass of the sun——was thought to be too turbulent for binary star systems to survive.
The discovery of D9 challenges this long-standing belief, suggesting that these regions may be more stable than previously assumed. “This is big news,” said Florian Peissker, lead author of the study and an astrophysicist at the University of Cologne.
He added that their discovery was fortuitous: “We are actually in a really lucky situation. We observed the system just in time.”
What To Know
The binary stars, known as D9, are estimated to be just 2.7 million years old——remarkably young by cosmic standards——and are positioned in a narrow zone of survival. Any further apart, the black hole’s immense gravitational force would tear them apart; any closer, the stars would merge into one.
“This leaves some questions still open,” said Anna Ciurlo, an astrophysicist at the University of California, Los Angeles, who was not involved with the study.
Using the Very Large Telescope (VLT) in Chile’s Atacama Desert, astronomers detected and measured the high velocities of the D9 stars. At first, the team believed they had found a single star, but further analysis revealed it to be a binary pair.
The stars reside within the S-cluster, a group of high-speed stellar bodies that whip around Sgr A* under its immense gravitational pull. The D9 system provides fresh insight into the nature of these regions, where stars can exist despite the influence of the black hole.
The discovery also sheds light on the “G objects” within the S-cluster——mysterious entities that appear to be clouds of gas and dust but behave like stars. Some scientists speculate that these objects may be the remnants of previous binary star mergers, suggesting that D9 could offer a glimpse into their origin.
What People Are Saying
Florian Peissker, lead author at the University of Cologne: “Our discovery lets us speculate about the presence of planets since these are often formed around young stars. It seems plausible that the detection of planets in the galactic center is just a matter of time.”
Emma Bordier, University of Cologne researcher: “This provides only a brief window on cosmic timescales to observe such a binary system——and we succeeded!”
Michal Zajaček, Masaryk University astrophysicist: “The D9 system shows clear signs of the presence of gas and dust around the stars, which suggests that it could be a very young stellar system that must have formed in the vicinity of the supermassive black hole.”
What Happens Next
Astronomers plan to use upgrades to the VLT and the forthcoming Extremely Large Telescope (ELT) to observe D9 and other objects within the S-cluster more closely.
These tools may also help confirm whether conditions near Sgr A* could allow planets to form around young stars like those in the D9 system.
The nature of the G objects and the evolution of binary systems in extreme gravitational fields remain ongoing questions, but discoveries like D9 bring astronomers closer to understanding how stars can exist—and thrive—near the heart of our galaxy.
This article includes reporting by The Associated Press
The post Twin Stars Spotted Orbiting Near Milky Way’s Supermassive Black Hole appeared first on Newsweek.
