Galactic collisions are events of breathtaking proportions. The supermassive black holes (SMBHs) at their centers plunge into a chaotic orbital dance that eventually coalesce into a single remnant. On their way to that point, they could eventually get “kicked” out of the center of their galaxy—and finding these “recoiling” black holes has been a challenge of cosmology for decades. A new paper, made available on the arXiv preprint server by an international team, used a novel idea to track down these fast-moving behemoths.
