The quasar is around 800 million times the mass of our sun.
New research about the orbit of supermassive black hole binaries could provide evidence for gravitational waves.
We have a long tradition of discovering cosmic features we weren't looking for in the first place.
NASA says it detected high-energy radiation that probably came from the collision of two black holes.
Scientists have observed gravitational waves passing through Earth, confirming one of the last predictions of Einstein's theory of general relativity.