duration/ Researchers at the University of Cologne and Masaryk University in Brno (Czech Republic) have discovered the fastest known star, which is orbiting a black hole in record time.
The star S4716 orbits the region of Sagittarius A*, the black hole at the center of our Milky Way, within four years, with a speed of regarding 8000 kilometers per second, according to the results of the study published in The Astrophysical Journal.
S4716 is regarding 100 astronomical units (AU) close to the black hole, which is a small distance by astronomical standards. One astronomical unit is equivalent to 149597870 kilometres.
Near the black hole at the center of our galaxy is a dense group of stars, called “S star clusters”, which are home to more than a hundred stars of varying brightness and mass. And the “S” stars move especially fast.
Dr Florian Bisker, lead author of the new study, said: ‘One of the prominent members, the star S2, behaves like a large person sitting in front of you in the cinema: it blocks your view of what’s important. Therefore, S2 often obscures the view to the center of our galaxy. However, in brief moments, we can observe the regions surrounding the central black hole.”
By constantly refining analysis methods, along with observations spanning nearly twenty years, scientists have now undoubtedly identified a star traveling around the central supermassive black hole in just four years.
A total of five telescopes observed the star, with four 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 and fast near a supermassive black hole was completely unexpected and represented the limit that can be observed with conventional telescopes,” Bisker said.
Moreover, this discovery sheds light on the origin and evolution of the orbit of fast-moving stars in the heart of the Milky Way.
“S4716’s short-range, compact orbit is very puzzling,” said Michael Zajek, an astrophysicist at Masaryk University in Brno who was involved in the study. “Stars cannot easily form near a black hole. S4716 had to move inward, for example By getting too close to stars and other objects in the S star cluster, it caused its orbit to shrink dramatically.”
