Rogue black hole spotted on its own for the first time

[Judi Lynn]

By Charles Q. Choi published about 7 hours ago

The isolated stellar-mass black hole is the first of its kind ever detected, scientists say.



This NASA illustration depicts a solitary black hole in space, with its gravity warping the view of stars and galaxies in the background. (Image credit: NASA’s Goddard Space Flight Center; background, ESA/Gaia/DPAC)

Astronomers may have for the first time detected and measured the mass of an isolated stellar-mass black hole, a new study finds.

Previous research suggested that when giant stars more than 20 times the mass reach the end of their lives, they usually die in catastrophic explosions known as supernovas, and their dense cores are expected to collapse to become black holes.

Stars big enough to create black holes are estimated to make up about one out of a thousand stars, suggesting that in the Milky Way, "there should be about 100 million stellar-mass black holes," study lead author Kailash Sahu, an astrophysicist at the Space Telescope Science Institute in Baltimore, told Space.com. (Stellar-mass black holes are up to a few times the sun's mass, as opposed to supermassive black holes millions of billions of solar masses large.)

Until now, all stellar-mass black holes detected to date have existed in binary systems with partners such as neutron stars. In contrast, the majority of the Milky Way's stellar-mass black holes should be singletons, Sahu said.

More:
https://www.livescience.com/rogue-black-hole-isolated

[Shermann]

1. I'm skeptical of the 100 million stellar-mass black hole approximation

This discounts the possibility of primordial black holes. They could be massive, stellar-mass, microscopic, or all (or none) of the above. Black holes could also hypothetically be the source of dark matter. Really that should be the leading candidate over the complete fabrication of new physics if you ask me.