One study has proposed that a dozen supermassive black holes roam the Milky Way and consume everything to their left.
Researchers at Harvard University simulated the formation and movement of supermassive black holes over billions of years of universal evolution.
They found that black holes become mostly rogue when their host galaxy collides with another galaxy, usually larger, and breaks the hole from its center point.
And the larger a galaxy, the more wandering black holes they’ve probably caught, with galactic clusters that can hold thousands.
“Don’t worry, the chances of us encountering a wandering supermassive black hole are very small,” paper author and astrophysicist Angelo Ricarte told MailOnline.
He added: “Space is so vast that even when two galaxies containing hundreds of billions of stars merge, their stars do not collide.”
Also, luckily for us, most rogue black holes end up merging with the supermassive black hole in the center of their new galaxy.
This means that those left, for example, in the Milky Way, usually come out into the galactic halo, far away from the location of our solar system.
“If there really was a supermassive black hole around us, we would be able to detect its presence from the movements of nearby stars,” Dr. Ricarte added.
One study has proposed that a dozen supermassive black hole channels (like the ones pictured) roam the Milky Way and consume everything in its path.
The more massive a galaxy, the more wandering black holes it will probably have caught, with galactic clusters (like the one in the image) that can house hundreds to thousands
Although regular black holes (those formed from the collapse of stars) usually have masses ranging from 5 to 20 times that of the sun, their supermassive counterparts can be millions or even thousands. millions of times heavier.
Supermassive black holes are usually found in the heart of galaxies, which act as anchors for the swirling mass of gas, dust, stars, planets, and other bodies around them. The Milky Way, for example, revolves around a so-called Sagittarius A *.
However, there are circumstances that can see these supermassive black holes come off the usual place and end up roaming free, as can happen as a result of a collision between galaxies.
In his new study, Dr. Ricarte and colleagues conducted a series of cosmological simulations called “ROMULUS” to track how the paths of wandering black holes could behave for billions of years.
At the beginning of each simulation, supermassive black holes were seeded based on local gas conditions, with bodies forming where the gas was poor in metals, dense (15 times the threshold to form a star), and warm ( at 9,500– 10,000 Kelvin).
These parameters are the same as those proposed for having formed the so-called “direct collapse” black holes when the Universe was young, at only about 100-250 million years old. (It is believed that the 13.77th anniversary has now passed).
In the simulation, this caused wandering black holes with a mass approximately one million times that of the sun.
In his new study, Dr. Ricarte and colleagues conducted a series of cosmological simulations called “ROMULUS” to track how the paths of wandering black holes could behave for billions of years. The team found that most of the rogue black holes in a galaxy came from the center of small satellite galaxies that collided with their larger host, leaving the massive body free of its main position. In the photo: a galaxy around the Milky Way mass has 15 rogue black holes (left), while one-tenth of the mass has only two vagrants (right)
The team found that most of the rogue black holes in a galaxy came from the center of small satellite galaxies that collided with their larger host, leaving the massive body free of its main position.
In addition, the number of stray black holes in a given galaxy tends to increase linearly with the mass of the galaxy, with the possibility that the Milky Way has about 12, but larger galaxies and clusters have more.
“We expect thousands of wandering black holes in the halos of galaxy clusters,” the researchers wrote in their article.
“Locally, these travelers account for about 10 percent of the local black hole mass budget once the seed masses are accounted for.”
In fact, according to researchers, in some early galaxies (about 12 billion years ago), wandering supermassive black holes may have even surpassed and surpassed their galactic center counterparts.
However, as time went on, many of these rogue black holes would have fused or absorbed into the supermassive black hole in the center of the new host galaxy, after first binary pairs formed as they slowly fell l to each other.
ROMULUS predicts that many supermassive black hole binaries form after several million years of orbital evolution, while some […] it will never reach the center, ”the researcher explained.
“As a result, it is found that the mass galaxies of the Milky Way at ROMULUS host an average of 12 SMBH that usually roam the halo away from the galactic center.”
“This analysis shows that our current census of supermassive black holes is incomplete and that there is likely to be a sizable population of off-center travelers,” the team concluded.
The full findings of the study were published in the Monthly Notices of the Royal Astronomical Society.