Black holes may be hiding just 150 light-years from Earth
A study suggests that two or three stellar-mass black holes could be hiding within the Hyades cluster, a group of stars located just 150 light-years away from Earth. This finding indicates that black holes may be much closer to our solar system than previously believed, providing valuable insight into the distribution of these mysterious objects across the Milky Way.
A little bit about the Hyades cluster of stars
Located in the constellation Taurus, the Hyades is an open cluster of stars that share the same characteristics and are loosely gravitationally bound. It is visible to the naked eye in the night sky. Estimated to be approximately 625 million years old, the cluster contains hundreds of stars. In the densely packed environments at their center, stars are expected to collide and merge at a higher rate than in less populated environments, leading to the formation of black holes.
Scientists compared data from Gaia spacecraft and simulations
To search for black holes in the Hyades cluster, astronomers compared observations from ESA's Gaia spacecraft and computer simulations. They analyzed certain parameters, one of them being the half-mass radius or the "radius within which half the cluster's mass is contained," per UniverseToday. "With the presence of some black holes, the cluster should be slightly more dense, and thus the half-mass radius should be smaller." Central density, which should spike if black holes are present, was another parameter.
Further research is needed to confirm the results
Based on the analysis, the team found that the best model predicts the presence of two or three stellar-mass black holes in the star cluster. However, more observations are needed to confirm these results.
Revealing hidden black holes in the Milky Way
The potential discovery of two or three stellar-mass black holes in the Hyades helps us better understand the invisible population of black holes in our home galaxy. Notably, these black holes could be over 10 times closer to our solar system than previously thought. "This observation helps us understand how the presence of black holes affects the evolution of star clusters and how star clusters in turn contribute to gravitational wave sources," said Mark Gieles, astrophysicist from University of Barcelona.
