September 2009 - Hubble and Chandra composite of the galaxy cluster MACS J0025.4–1222
This spectacular view of galaxy cluster MACS J0025.4–1222 combines images from Hubble and the Chandra X-ray observatory and demonstrates how ordinary matter and mysterious dark matter interact. The blue cloud-shaped regions show the position of dark matter and the pink central cloud indicates the presence of ordinary matter.
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NASA, ESA, CXC, M. Bradac (University of California, Santa Barbara, USA), and S. Allen (Stanford University, USA)