One of only two known supermassive black hole binary systems has been found by a team of researchers from Purdue University and other universities. The two black holes that circle each other are anticipated to be 100 million suns in size. One of the black holes propels a gigantic jet outward at almost the speed of light. Because the system is so far away, the visible light we see now was released 8.8 billion years ago.
The two are only 200 to 2,000 AU apart (one AU equals the distance between the Earth and the sun), which is at least ten times closer than the only other known supermassive binary black hole system.
The near proximity is crucial since such systems are likely to join at some point. That explosion will unleash vast amounts of energy in the form of gravitational waves, generating ripples in space in all directions (as well as oscillations in matter) as the waves pass through.
Finding systems like these is also vital for understanding how galaxies evolve and how they end up with huge black holes at their cores.
The system was found by chance when researchers identified a recurring sinusoidal pattern in its radio brightness emission fluctuations over time, based on data collected after 2008. A later check of historical data indicated that the system was also fluctuating in the late 1970s and early 1980s. That kind of change is precisely what experts would predict if the jetted emission from one black hole is altered by the Doppler effect as it swings around the other black hole owing to orbital motion.
From 2002 to 2012, Purdue University’s College of Science’s Matthew Lister and his colleagues observed the system, however the team’s radio telescope lacks the sensitivity to discern the individual black holes at such a great distance. His imaging data confirms the binary black hole theory while also providing the orientation angle of the jetted outflow, which is an important component in the paper’s model for Doppler-induced fluctuations.