Scientists have named a pair of merging supermassive black holes after locations from J.R.R. Tolkien's 'The Lord of the Rings.' The beacons of these quasars, when lit, indicate the presence of binary black holes, providing a method for scientists to map these cosmic mergers. This discovery, made by the NANOGrav team, offers the first concrete benchmarks for developing and testing detection protocols for individual, continuous gravitational wave sources. The team used their new approach to search for supermassive black hole binaries in 114 Active Galactic Nuclei (AGNs), the bright central regions of galaxies where black holes feast on surrounding gas and dust. The names 'Rohan' and 'Gondor' were chosen to honor the Yale student who first analyzed the data and the iconic scene from the novel, respectively. This research could help scientists understand galaxy mergers, black hole physics, and the nature of gravitational waves, and it has laid out a roadmap for a systemic supermassive black hole binary detection framework.
