The Gaia mission, with the participation of Spain, discovered the most massive black hole in the Milky Way

It was named as Gaia BH3 (BH3) and it’s a big black hole, with a mass almost 33 times that of the Sun, which was hiding less than 2000 light years from Earth, in the constellation Aquila. The mission’s team of Spanish astronomers and engineers from the Department of Quantum Physics and Astrophysics, the Institute of Space Sciences (ICCUB) of the University of Barcelona and the Institute of Space Research of Catalonia (IEEC) discovered ESA’s Gaia, the European Space Agency’s most ambitious project yet. study the history and structure of the Milky Way.

What kind of black hole is this?

Black holes are divided into three types depending on their mass: stellar, supermassive and intermediate masses, and each type plays a unique role in the cosmic ballet of the Universe. Stellar black holes are the most common and appear when massive stars, at least 20 times the mass of our Sun, run out of their nuclear fuel and collapse under their own gravitational pull. Supermassive black holes have been found at the heart of almost all large galaxies, including our Milky Way. Sagittarius A*.

These colossal objects typically have a mass equivalent to millions or even billions of suns and have a significant impact on the environment. Finally, intermediate-mass black holes would be the middle children of a family of black holes with masses ranging from one hundred to several hundred thousand solar masses (they could reach a million solar masses) and represent a hypothetical class of black holes. The black hole recently discovered by the Gaia mission is precisely stellar mass black hole.

Stellar mass hole

BH3, formed by a supernova explosion of a very massive star, was first discovered by the European Space Agency’s Gaia mission.

“No one expected to find a huge black hole lurking nearby.has not yet been discovered,” explained Pasquale Panuzzo, an astronomer at the Paris Observatory, part of the National Center for Scientific Research (CNRS) of France, and co-author of the paper published in the journal. Astronomy and astrophysics. “This is a once-in-a-lifetime discovery,” added Panuzzo, a member of the Gaia collaboration. But this was not only Gaia’s mission. Several telescopes have confirmed the existence of BH3, as have ground-based observatories, including Very Large Telescope European Southern Observatory in Chile.

Its mass is almost 33 times that of the Sun, and it was hiding less than 2,000 light years from Earth, in the constellation Aquila. This is the first stellar-origin black hole large enough to be discovered so close to our planet. The discovery of Gaia BH3 is very exciting precisely because of its mass. Until now, black holes of this mass have only been discovered in distant galaxies. In fact, BH3’s closest competitor is the black hole Cygnus X-1, which has 21 times the mass of our Sun (by comparison, Sagittarius A* contains four million times the mass of the Sun).

How was it formed?

But that is not all. Ground-based telescopes have also detected a “strange wobble” in the stellar black hole’s companion star. very metal poor starwhich suggests that Gaia BH3 formed from a similar star, also metal-poor (so named due to its low abundance of heavy elements).

“The UVES (VLT Visual Ultraviolet and Echelle Spectrograph) 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,” they comment. official press release.

This type of star is thought to lose less mass during its stellar life cycle. “That’s why, They have more material left to create high-mass black holes. after his death,” the authors note.

“This is a real unicorn! This is unlike anything we have ever seen,” concluded Pasquale Panuzzo of the Paris Observatory of the National Center for Scientific Research (CNRS) in France and lead author of the paper. “You can only make such a discovery once in your entire research life. Until now, the LIGO-Virgo-KAGRA collaboration has only discovered such large black holes in distant galaxies through observations of gravitational waves.”

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