By combining deep Chandra observations with data from Hubble, Spitzer, and other telescopes, astronomers have identified 28 black holes in an area of the sky that were previously classified differently. These black holes are circled in the Chandra Deep Field-South image, where red, green, and blue represent the low, medium, and high-energy X-rays that Chandra detects.

These artist's illustrations depict how these black holes are wrapped in cocoons of material, making it difficult to accurately identify them. The cocoon (red) surrounds a disk of material falling onto the black hole, plus a wind of material (blue) blowing away from the disk. A portion of the cocoon is cut out to show the heavily obscured black hole. This discovery has important implications for understanding how supermassive black holes grow and evolve over billions of years.