This is the first stellar-mass black hole ” dormant” to be unambiguously spotted outside our galaxy.
This artistic illustration shows what the VFTS 243 binary system would look like if we observed it closely. The lens effect around the black hole is only shown to make this object more visible in the image.
A mass black hole stellar cloud has been detected in the Large Magellanic Cloud, a neighboring galaxy to our Milky Way.
The spotting was carried out by an international team of astrophysicists following six years of observations carried out with the Very Large Telescope of the European Southern Observatory (ESO) installed in the desert. Atacama, Chile.
The Milky Way and the two Magellanic clouds.
We have identified a needle in a haystack, said Tomer Shenar of the University of Amsterdam in the Netherlands in a statement.
The celestial object has a mass about nine times greater than the Sun and orbits a hot blue star 25 times the mass of our star.
< p class="e-p">There are several types of black holes, those celestial objects which possess an extremely large mass in a very small volume and whose gravitational field intensity prevents any form of matter or radiation from escaping.
VFTS 243 is a stellar black hole, objects that form during the gravitational collapse of massive end-of-life stars that usually explode as supernovae. To date, 20 such black holes have been confirmed in the Milky Way.
- Primordial black holes are very small. They would have formed during the big bang in the extremely dense regions of the primordial universe.
- Intermediate black holes oscillate between 100 and 10,000 solar masses.
- Stellar black holes have a mass 10 to 20 times that of the Sun.
- Supermassive black holes are found at the center of most galaxies, and their masses are millions or even billions of times that of the Sun. The one in the center of the Milky Way is called Sagittarius A*, the first image of which was made public last May.
The recently spotted black hole is believed to have originated in a system of two stars revolving around each other, a process that left behind a black hole orbiting a bright companion star, notes Pablo Marchant of KU Leuven University, Belgium, one of the study's co-authors.
A black hole is considered dormant if it does not emit high levels of X-rays. These celestial objects are very difficult to spot, as they interact very little with their surroundings.
To successfully detect VFTS 243, scientists scanned 1,000 massive stars in the Tarantula Nebula region of the Large Magellanic Cloud for companion black holes operating in a binary system of stars.
The black hole is some 160,000 light-years from Earth.View larger
On this image appears the Tarantula Nebula. It reveals a celestial landscape of star clusters, gas clouds and remnants of supernovae explosions.
This work also makes it possible to better understand the processes that lead to the appearance of black holes. Astronomers believe that a stellar-mass black hole forms when the core of a dying massive star collapses, but it's unclear whether or not this process is accompanied by #x27;a powerful supernova explosion, the authors note.
In this case, the star that gave birth to the black hole appears to have collapsed entirely , with no sign of an earlier explosion.
“Evidence for this direct collapse scenario has emerged recently, but our study provides arguably one of the most direct indications . This has huge implications for the origin of black hole mergers in the cosmos. »
— Tomer Shenar, University of Amsterdam
Details of this work are published in the journal Nature Astronomy .
Last January, Italian astrophysicists estimated the number of stellar black holes in the observable Universe at around 40 trillion. This number is equivalent to 40 billion billion (4 and 19 zeros).
American colleagues estimated in 2017 that the Milky Way alone contained around 100 million.