The Chandra X-ray Telescope captured this image of hot gas (green) in the core of the 2.4 billion light-year distant galaxy cluster, Abell 520. The million degree gas is evidence of a recent massive collision within the cluster. Credit: NASA, ESA, CFHT, CXO, M.J. Jee (University of California, Davis), and A. Mahdavi (San Francisco State University)
X-rays from gas in a galactic collision.
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