All the other properties of these massive dying stars, like their detailed composition, density and temperature profiles, disappear as they transform into a black hole. That is how simple they are.

Figuring out whether a galaxy has one or two black holes in its center isn’t as easy as cracking an egg and examining the yolk. But measuring how often these binary supermassive black holes form ...

Yet the physics-breaking power of the space-time ruptures is also part of their draw — sucking in scientists who want to study the role of black holes in sculpting galaxies and those searching ...