Binary star found near our galaxy’s supermassive black hole
An international team of researchers has discovered a binary star orbiting close to Sagittarius A*, the supermassive black hole at the center of the Milky Way. This is the first time a pair of stars has been discovered near a supermassive black hole. The discovery, based on data collected by the European Southern Observatory’s Very Large Telescope (ESO’s VLT), helps us understand how stars survive in extreme gravity environments and may pave the way for the detection of planets close to Sagittarius A*.
“Black holes are not as destructive as we thought,” said Florian Peißker, a researcher at the University of Cologne in Germany and lead author of the study published today in Nature. nature communications. Binary stars, pairs of stars that orbit each other, are common in the universe, but they have never before been found near supermassive black holes, where strong gravity can destabilize star systems.
The new discovery shows that some binary stars can thrive briefly even under destructive conditions. The newly discovered binary star D9 was discovered just in time: its age is estimated to be only 2.7 million years, and the strong gravity of a nearby black hole will likely cause it to merge into a single star in a short period of time. Ten thousand years is a very narrow time span.
“This only provides a brief window on cosmic timescales to observe such a binary system – and we succeeded!” co-author Emma Bordier, researcher at the University of Cologne and former student at the European Southern Observatory explain.
For years, scientists have also thought that the extreme conditions near supermassive black holes hinder the formation of new stars. The discovery of several young stars near Sagittarius A* has refuted this hypothesis. The discovery of this young binary shows that even stellar pairs can form under these harsh conditions. “The D9 system shows clear signs of gas and dust surrounding the star, suggesting that it may be a very young star system that must have formed near a supermassive black hole,” explains co-author Michal Zajaček. University and researcher at the University of Cologne.
The newly discovered binary star was discovered in a dense cluster of stars and other objects known as the S Cluster orbiting Sagittarius A*. The most mysterious of the cluster are G objects, which behave like stars but appear like clouds of gas and dust.
It was while observing these mysterious objects that the team discovered surprising patterns in D9. Data obtained by the VLT’s ERIS instrument, combined with archival data from the SINFONI instrument, revealed repeated changes in the stellar velocity, indicating that D9 is actually two stars orbiting each other. “I think my analysis was wrong,” Peißker said, “but the spectral pattern covers about 15 years, and it is clear that this detection is indeed the first binary star observed in the S cluster.”
The research results provide new clues to the existence of mysterious G objects. The team proposes that they may actually be a combination of binary stars that have not yet merged and leftover material from merged stars.
The exact nature of the many objects orbiting Sagittarius A*, and how they formed so close to the supermassive black hole, remains a mystery. But soon, the GRAVITY+ upgrade of the VLT interferometer and METIS instrument on ESO’s Extremely Large Telescope (ELT), which is under construction in Chile, may change this situation. The two facilities will allow the team to conduct more detailed observations of the Milky Way’s center, revealing the properties of known objects and undoubtedly discovering more binaries and young systems. “Our discovery allows us to speculate on the existence of planets, since these planets usually form around young stars. It seems to be only a matter of time before a planet is discovered at the center of the Milky Way,” Peckel concluded.
2024-12-17 18:09:04