The black holes they come in a variety of sizes, from stellar black holes a few times the mass of the sun to supermassive black holes, which are millions of times the mass of the sun and lurk at the heart of galaxies. Astronomers recently discovered a massive black hole just 1,550 light-years away, which is right in our neighborhood, astronomically speaking. It is one of the closest black holes ever discovered, with a mass 12 times that of the Sun. Being so close to us, it is an exciting target for future research.
“It is closer to the sun than any other known black hole, at a distance of 1,550 light-years,” Sukanya Chakrabarti, lead author of the study from the University of Alabama at Huntsville, said in a blog post. release. “So, it’s practically in our backyard.”
The black hole was discovered using data from NASA’s Gaia mission. European Space Agency, which is building a 3D map of the entire galaxy. The researchers looked at almost 200,000 binary stars, in which one star orbits a companion, to look for cases where the brightness of one star was enough to explain the brightness of the binary. That implies that the companion in these binaries must be dark, suggesting that the companion could be a black hole.
The researchers then took these selected binaries and studied the Doppler shift of their light, which shows how massive the companion must be and gives information about the pair’s orbit and rotation. This is how they identified and learned about the nearby black hole.
“In this case, we’re looking at a monster black hole, but it’s in a long-period orbit of 185 days, or about half a year,” Chakrabarti said. “It is quite far from the visible star and does not make any progress towards it.”
In addition to finding a useful target for research due to its location, the study also demonstrates how more black holes may be identified in the future.
“Simple estimates suggest that there are about a million visible stars that have companion massive black holes in our galaxy,” Chakrabarti said. “But there are a hundred billion stars in our galaxy, so it’s like looking for a needle in a haystack. The Gaia mission, with its incredibly precise measurements, made it easier by narrowing down our search.”
The research has not yet been peer-reviewed, but has been submitted to The Astrophysical Journal.