Stars tens of times heavier than our Sun don't die as thought before. Computer models show that their core often doesn't ignite a supernova, but quickly collapses into a black hole. Imagine a soufflé: the center suddenly sinks, and almost all the batter falls into the funnel, with just a few drops splashing out. Same for a star: most of its matter falls inward instead of flying away.
In 23 simulations of stellar death, in 18 cases the hole formed before the explosion could blow off the outer layers. This happened for stars 19–60 times heavier than the Sun. We used to think only the most massive stars collapsed this way, but simulations prove otherwise.
The most surprising part: the final mass of the black hole weakly depends on the size of the carbon core. A lighter star can give birth to a heavier hole than a more massive one. Simulations showed: even after collapse, some matter escapes, producing a dim flash. Its light, bending around the hole, turns into a ghostly ring for an observer.
A black hole's mass can reach 26 solar masses — that's like squeezing nine million Earths into an invisible point, around which light wraps into a ring.