Bright X-ray flares were being observed emerging from a supermassive black hole which lies at the centre of a galaxy 800 million light-years away, an intriguing but not unique phenomenon.
However, additional flashes of X-rays that were smaller, later and of different 'colours' than the bright flares were later detected that were much more unexpected by the scientists. These were dubbed “luminous echoes”, which according to theory are consistent with X-rays reflected from behind the black hole.
“Any light that goes into that black hole doesn’t come out, so we shouldn’t be able to see anything that’s behind the black hole,” said Stanford University astrophysicist Dan Wilkins. “The reason we can see that is because that black hole is warping space, bending light and twisting magnetic fields around itself.”
The strange discovery is believed to be the first direct observation of light from behind a black hole – a scenario that was predicted by Einstein...