Newly discovered nearby black hole

[stevebowers]

Lots of strange characteristics about this star. Probably from another galaxy, and the remaining star seems to have been captured later.

The star orbiting Gaia BH3 at about 16 times the Sun–Earth distance is rather uncommon: an ancient giant star, that formed in the first two billion years after the Big Bang, at the time our galaxy started to assemble. It belongs to the family of the Galactic stellar halo and is moving in the opposite direction to the stars of the Galactic disc. Its trajectory indicates that this star was probably part of a small galaxy, or a globular cluster, engulfed by our own galaxy more than eight billion years ago.
The companion star has very few elements heavier than hydrogen and helium, indicating that the massive star that became Gaia BH3 could also have been very poor in heavy elements. This is remarkable. It supports, for the first time, the theory that the high-mass black holes observed by gravitational wave experiments were produced by the collapse of primeval massive stars poor in heavy elements. These early stars might have evolved differently from the massive stars we currently see in our galaxy.
The composition of the companion star can also shed light on the formation mechanism of this astonishing binary system. "What strikes me is that the chemical composition of the companion is similar to what we find in old metal-poor stars in the galaxy,” explains Elisabetta Caffau of CNRS, Observatoire de Paris, also a member of the Gaia collaboration.
“There is no evidence that this star was contaminated by the material flung out by the supernova explosion of the massive star that became BH3.” This could suggest that the black hole acquired its companion only after its birth, capturing it from another system."