In our nearby Large Magellanic Cloud galaxy, a recently found black hole has been hidden in a cluster of thousands of stars. The black hole is 160,000 light-years distant from Earth and has a mass 11 times our sun.
Astronomers discovered it by measuring how the gravity of a nearby star, roughly five times the mass of our sun, was impacted by the European Southern Observatory’s Very Large Telescope in Chile. This is the first time this method of finding a black hole has been employed, and it might aid researchers in discovering more hidden black holes in our Milky Way galaxy and other galaxies.
The more scientists discover black holes, the more they will comprehend how these cosmic phenomena grow and evolve through time. The Royal Astronomical Society has approved a manuscript presenting this finding for publication.
In a statement, Sara Saracino, research lead and a member of the faculty of engineering and technology at Liverpool John Moores University, said, “Like Sherlock Holmes finding a criminal gang from their evidence, we are looking at every single star in this cluster with a magnifying glass in one hand, trying to find some evidence for the presence of black holes but without seeing them directly.”
The result presented below reflects only one of the sought offenders, but Saracino said that once you’ve located one, you’re well on your way to finding many more in other clusters.
While black holes might be challenging to detect, their movements tend to reveal their otherwise undetectable presence. When black holes consume surrounding stuff, they emit X-rays, and when they collide or collide with dense neutron stars, they generate gravitational waves.
However, there are different black holes, and this one is smaller than some of the others discovered by astronomers. The researchers only noticed it when they noticed a star with unusual motion among many other celebrities who weren’t acting the same way. According to Stefan Dreizler, research co-author and professor at Germany’s University of Göttingen, “the great majority (of black holes) can only be revealed dynamically.”
When they create a system with a star, they impact its speed in a modest but observable way, allowing us to locate them using advanced sensors. This is the first young black hole amid a cluster of equally young stars, roughly 100 million years old, which is infancy compared to the rest of the universe.
In the future, scientists might use this approach to locate more juvenile black holes to understand their evolution better and compare them to larger black holes in older star clusters to discover how black holes evolve through time. “Every single detection we make will be critical for our future knowledge of star clusters and the black holes that inhabit them,” said Mark Gieles, study co-author and research professor at the University of Barcelona in Spain, in a release.
The scientists utilized data acquired over two years with the Multi-Unit Spectroscopic Explorer (MUSE) installed at ESO’s VLT in Chile’s Atacama Desert to conduct their search. MUSE enabled us to study densely packed locations, such as the core regions of stellar clusters, by examining the light of every single star in the surrounding. According to co-author Sebastian Kamann, a long-time MUSE expert based at Liverpool’s Astrophysics Research Institute, the net result is information about thousands of stars in a single shot, at least ten times more than with any other sensor. This enabled the scientists to identify the unusual star whose strange motion indicated the presence of the black hole.