The disk of gas that spirals onto a newborn magnetar wobbles, creating "bumps" in the brightness of the supernova that accompanied this object's birth.
Most galaxies have a supermassive black hole at their center, but some galaxies have two. These supermassive binaries form when two galaxies collide and merge. We can detect some of these binaries, such as by observing the periodic changes of a quasar or by observing the binary directly, such as in the case of NGC 7727. But most supermassive binaries remain hidden. They are too far away to be observed directly or too inactive to be observed by jets. And while gravitational wave observatories can detect the mergers of stellar-mass black holes, we can't yet detect the mergers of supermassive black holes. But a new study shows how we might detect some of them.
