A group of astronomers have found the most massive stellar mass black hole ever discovered in our galaxy, and it is “extremely close” to Earth, according to new research they have released. The work is based on the discoveries of black holes by European Space Agency (ESA) mediating its Gaia mission. When researchers refer to its proximity to Earth, they do so in the sense of astronomical distances. The black hole, called Gaia BH3, is 33 times more massive than our Sun, just as report Live Science.
It is not the most massive black hole in our galaxy: that title belongs to Sagittarius A, the supermassive black hole at the center of the Milky Way, which is about four million times the mass of the Sun. But Gaia BH3 is the hole most massive black known in the Milky Way that formed from the collapse of a star.
Cygnus X-1, the next largest known stellar black hole in our galaxy, weighs only 21 solar masses. The newly discovered black hole is located about 2,000 light years away, in the constellation Aquila., making it the second closest known black hole to Earth. These findings were published on April 16 in the journal Astronomy and Astrophysics.
“No one expected to find a massive black hole lurking nearby, undetected until now”Pasquale Panuzzo, a member of the Gaia collaboration and an astronomer at the Paris Observatory, which is part of France’s National Center for Scientific Research (CNRS), said in a statement. For Panuzzo this is the kind of once-in-a-lifetime research discovery.
Black holes formed by the collapse of massive stars
This black hole was detected in data from the European Space Agency’s Gaia mission because generates a strange “wobble” motion to the companion star orbiting it. Data from the Very Large Telescope (VLT) of the European Southern Observatory (ESO) and other ground-based observatories were used to verify the mass of the black hole, which, as we indicated, is 33 times greater than that of the Sun.
Stellar black holes form from the collapse of massive stars and those previously identified in the Milky Way are, on average, about 10 times more massive than the Sun. Therefore, this new observation of 33 solar masses is exceptional. Surprisingly, this black hole is also very close to us: just 2,000 light-years away. Dubbed Gaia BH3 or BH3 for short, it was found while the team was reviewing Gaia observations in preparation for an upcoming data release.
Among the terrestrial confirmation data used are those from the Ultraviolet and Visual Echelle Spectrograph (UVES) instrument, located in the Chilean Atacama Desert.. These observations revealed key properties of the companion star that, together with data from Gaia, allowed astronomers to accurately measure the mass of BH3. Astronomers have found similarly massive black holes outside our galaxy, using a different detection method, and have theorized that they could form from the collapse of stars with very few elements heavier than hydrogen and helium in their chemical composition.
Unique discovery
Stars in pairs tend to have similar compositions, meaning BH3’s companion contains important clues about the star that collapsed to form this exceptional black hole. The data showed that the companion was a very metal-poor star, indicating that the star that collapsed to form BH3 was also metal-poor.just as predicted.
“We have taken the exceptional step of publishing this paper based on preliminary data ahead of the upcoming Gaia publication due to the unique nature of the discovery“, says co-author Elisabetta Caffau, also a member of the Gaia collaboration at the CNRS Observatory in Paris. The early publication of the data will allow other astronomers to start studying this black hole right now, without waiting for the planned publication of the complete data. by the end of 2025 at the earliest.
Stars in pairs tend to have similar compositions, meaning BH3’s companion holds important clues about the star that collapsed to form this rare black hole.. The data showed that the companion was a very metal-poor star, indicating that the star that collapsed to form BH3 was also metal-poor, as predicted.
