X-ray vision
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Credit: NASA, ESA, ESO, CXC, and D. Coe (STScI)/J. Merten (Heidelberg/Bologna)
Red colours show the X-rays from hot gas in the galaxy cluster Abell 2744. The X-ray data were collected by NASA’s Chandra X-ray Observatory; the background image was taken by the Hubble Space Telescope photo. Blue colours map the distribution of colder dark matter.