Hundreds of rogue black holes seen lurking in the Milky Way could swallow Earth.
According to a study, dozens of rogue supermassive black holes in the Milky Way have the capacity to engulf the Earth, although experts think the possibilities are still tiny.
Harvard University researchers discovered that black holes go rogue when their host galaxy collides with another, usually larger, galaxy, knocking the hole out of its center position.
This was discovered by modelling the birth and movement of supermassive black holes across billions of years of cosmic evolution. They achieved it by executing a series of cosmological simulations known as ROMULUS, which followed the pathways of wandering black holes.
Supermassive black holes were seeded based on local gas conditions at the start of each simulation, with the bodies forming when the gas was metal-poor, dense (15 times the threshold for generating a star), and warm (at 9,500–10,000 Kelvin).
This resulted in wandering black holes with a mass of one million times that of the sun in the simulation.
The larger the galaxy, the more wandering black holes it is likely to have gathered up, with galactic clusters capable of containing thousands.
“Don’t panic, the chances of us encountering a wandering supermassive black hole are vanishingly small,” the paper’s author and astrophysicist Angelo Ricarte stated.
“Because space is so wide, even when two galaxies with hundreds of billions of stars unite, their stars do not collide.”
Observational evidence suggests that practically every giant galaxy has a supermassive black hole at its center.
Supermassive black holes are very dense regions in the center of galaxies, with masses billions of times that of the sun.
They serve as anchors for the whirling mass of gas, dust, stars, planets, and other stuff that swirl around them.
Sagittarius A is the center of the Milky Way galaxy.
Fortunately, the vast majority of renegade black holes eventually merge with the supermassive black hole at the center of their new galaxy.
Those who survive — for example, in the Milky Way – are likely to be far out in the galactic halo and far away from our own solar system.
“If there was a supermassive black hole close in our neighborhood, we would be able to identify its presence from the motions of adjacent objects,” Dr Ricarte continued.