Researchers at the German Universities of Cologne and the Czech Masaryk have discovered the fastest known star orbiting a black hole in record time.
The star is registered as “S4716”, and it revolves around the black hole in the center of our Milky Way galaxy, within 4 years, and its speed reaches about 8 thousand kilometers per second.
According to the study published in The Astrophysical Journal, the star “S4716” approaches the black hole by 100 AU (astronomical unit), which is a small distance by astronomical standards.
Near the black hole in the center of our galaxy there are dense groups of stars, and the S group, home to more than 100 stars that vary in their brightness and mass, and the stars of this group move at a special speed.
Dr Florian Bisker, lead author of the study, said: “One prominent member of that group is the star, S2, which acts like a large person sitting in front of you in the cinema, blocking your view of what’s important. S2 often blocks your view of the center of our galaxy. For a brief moment, we can observe the regions surrounding the central black hole.”
By constantly refining analysis methods, along with observations spanning nearly 20 years, the world has now undoubtedly identified a star that travels around the central supermassive black hole in just 4 years.
A total of 5 telescopes observed the star, with 4 of these five being combined into one large telescope to allow for more accurate and detailed observations.
“The presence of a star in a stable orbit very close, very fast, near a supermassive black hole was completely unexpected and represented the limit that could be observed with conventional telescopes,” says Florian Bisker.
Moreover, this discovery sheds light on the origin and evolution of the orbit of fast-moving stars in the heart of the Milky Way, where the short-range, compressed orbit of the star (S4716) seems very confusing, as stars cannot easily form near a black hole, says Michael Zajek, An astrophysicist at Masaryk University who participated in the study.