Compared to the drawn-out chirps of black hole binaries on decaying orbital spirals, it was a sharp crack. The best explanation of the event, named GW190521, was a chance encounter of two black holes snaring each other in passing. They also constructed a waveform for a standard binary black hole merger to compare against the observation data. The binary black hole merger waveform was a slightly better fit for the observed signal than the wormhole waveform – but only slightly. The most massive black hole merger to date, GW231123, produced an object 225 times the mass of the Sun.