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This image of Abell 2261 contains X-ray data from Chandra (pink) showing hot gas pervading the cluster as well as optical data from Hubble and the Subaru Telescope that show galaxies in the cluster and in the background. Astronomers used these telescopes to search galaxy in the center of the image for evidence of a black hole, weighing between 3 and 100 billion times the Sun, that is expected to be there. No sign of this black hole was found, deepening a mystery about what is happening in this system.