The mystery surrounding the whereabouts of a supermassive black hole has deepened, researchers say. Despite searching with NASA’s Chandra X-ray Observatory and Hubble Space Telescope, astronomers have no evidence that a distant black hole estimated to weigh between 3 billion and 100 billion times the mass of the sun is anywhere to be found. This missing black hole should be in the enormous galaxy in the center of the galaxy cluster Abell 2261, which is located about 2.7 billion light-years from Earth. Nearly every large galaxy in the universe contains a supermassive black hole in their center, with a mass that is millions or billions of times that of the sun.