Abell 2218: A Galaxy Cluster Lens . ... Credit Copyright: W. Couch (University of New South Wales) , R. Ellis (Cambridge University), NASA Explanation: Gravity can bend light . Almost all of the bright objects in this Hubble Space Telescope image are galaxies in the cluster known as Abell 2218. The cluster is so massive and so compact that its gravity bends and focuses the light from galaxies that lie behind it. ... NASA Web Site Statements, Warnings, and Disclaimers . ...