A colossal flare could be the first evidence energy can be extracted from black holes.
a rotating black hole generates vast amounts of energy, which, theoretically, can be extracted from the ergosphere, a region that sits just on the outside of the event horizon. This has been shown both theoretically and experimentally – and now a team of astrophysicists has found what they believe is observational evidence for it.
For more, check out this Science Alert/MSN story.