Tapping the Well

M. Weiss / Harvard-Smithsonian Center for Astrophysics In this artist’s conception, the black hole at the center of our galaxy is surrounded by a hot disk of accreting material. Blue lines trace magnetic fields. Galactic black holes are cosmic mitochondria, powerhouses of the Universe. Most of the energy these supermassive black holes produce is through the material surrounding them. Superheated plasma of their accretion disks interacting with tremendous magnetic fields. But there is a more direct way to extract energy from a black hole. It’s known as the Penrose process, and a new study asks whether we could discover a signature of this process.1 First proposed by Roger Penrose in 1969, the mechanism describes how you could extract energy directly from a rotating black hole, thus decreasing its total mass.2 This is different from the usual mechanism where black holes generate power as a by-product of consuming matter and increasing mass. It relies on a feature of rotating black holes…