... The El Gordo Massive Galaxy Cluster . ... The above image of El Gordo is a composite of a visible light image from the Hubble Space Telescope , an X-ray image from the Chandra Observatory showing the hot gas in pink, and a computer generated map showing the most probable distribution of dark matter in blue, computed from gravitational lens distortions of background galaxies. ... Publications with keywords: galaxy cluster - dark matter . Publications with words: galaxy cluster - dark matter . ...