That's what our Patreon supporter Aaron Weiss wants to know, asking:How [is] angular momentum conserved when stars collapse to black holes? To anything that falls inside, however, it inevitably gets brought towards the very center of this black hole: towards a singularity. And, perhaps most importantly, all stars we've ever discovered spin, and angular momentum is always conserved, so black holes should be spinning, too. When a black hole rotates, however, it gets dragged around through all three dimensions, where it will fill a torus-like region surrounding the black hole's equator. As more black holes are imaged and more and improved observations come in, we fully expect to learn even more about the physics of real, spinning black holes.

Source: Forbes April 20, 2019 06:00 UTC