“Take the Solar System, put a black hole where the Sun is, and the Sun where the Earth is.”
Maybe that’s the easiest way to explain the black hole Gaia BH1, which is also closest black hole to Earth.
The black hole was recently discovered by a group of astronomers with the help ofThe Gemini North Telescope, located in Hawaii. Experts detail that this black hole close to our planet is idle.
The black hole weighs about 10 times the mass of the Sun and is located approximately 1,600 light-years away in the constellation Ophiuchus, making it three times closer to our planet.
The new discovery was made possible by precise observations of the motion of the black hole’s companion, a Sun-like star orbiting it at roughly the same distance as the Earth from the Sun.
“Take the Solar System, put a black hole where the Sun is, and the Sun where the Earth is, and as a result you will have this particular System,” explained Kareem El-Badry, an astrophysicist at the Harvard & Smithsonian Center for Astrophysics and the Max Institute. Planck of Astronomy.
Kareem El-Badry is the lead author of the scientific paper describing the discovery.
“While there have been many detections of systems like this, almost all of these discoveries have since been refuted. Instead, this is the first unequivocal detection of a Sun-like star in a wide orbit around a stellar-mass black hole in our galaxy”, he added.
The astronomers explain that while there are likely millions of stellar-mass black holes wandering the Milky Way, the few detected were discovered by their interactions with a companion star.
As material from a nearby star spirals toward the black hole, it begins to heat up, generating powerful X-rays and jets of material. But if a black hole isn’t feeding (that is, it’s inactive), it simply blends in with its surroundings.
El-Badry said he has searched for dormant black holes for the past four years using a wide variety of methods and different data sets.”
“My previous attempts, as well as other people’s, have resulted in a collection of binary systems posing as black holes, but this is the first time the search has paid off,” he said.
The team of researchers reported that they originally identified the system as potentially harboring a black hole, by analyzing data from the European Space Agency’s Gaia spacecraft, which had captured tiny irregularities in the star’s motion caused by gravity. of an invisible and massive object.
To explore the system in greater detail, El-Badry and his team made follow-up observations using the Multi-Object Spectrograph instrument on Gemini North, which were crucial in allowing them to identify the central body as a black hole about 10 times more massive than our Sun.
“Our follow-up observations with Gemini confirmed beyond reasonable doubt that the binary system contains a normal star and at least one dormant black hole,” El-Badry explained.
Astronomers’ current models of the evolution of binary systems cannot fully explain how the peculiar configuration of the Gaia BH1 system came about, because the original star that later became this black hole should have been at least 20 times more massive than our Sun.
This means that it would have lived only a few million years. If both stars formed at the same time, this massive star would have rapidly become a supergiant, inflating and engulfing the other star before it had time to become a proper main-sequence star, burning hydrogen just like our own. Sun.
In their statement, the specialists state that it is not entirely clear how the solar-mass star survived to that episode, ending up as an apparently normal star, just as observations indicate. All theoretical models that allow for this survival, they explain, predict that the solar-mass star should be in a much tighter orbit than is actually observed.
“It is interesting to see that this system does not fit easily into standard models of binary evolution, because it raises a lot of questions about the formation of this binary system, as well as how many of these dormant black holes exist,” El-Badry concluded.