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The European Space Agency reports that a “monster” black hole that was dormant for 26 years has once again begun “devouring” material from the star in its system. V404 Cygni, a system in the Milky Way galaxy comprised of a black hole and a star orbiting each other, has begun emitting X-rays and gamma rays. “The behavior of this source is extraordinary at the moment, with repeated bright flashes of light on time scales shorter than an hour, something rarely seen in other black hole systems,” said Erik Kuulkers, a project scientist at ESA. “In these moments, it becomes the brightest object in the X-ray sky—up to fifty times brighter than the Crab Nebula, normally one of the brightest sources in the high-energy sky.”