Wide field image of galaxy cluster SDSS J1110+6459

The galaxy cluster shown here, SDSS J1110+6459, was discovered as part of the Sloan Giant Arcs Survey. It is located about 6 billion light-years from Earth ( redshift of z=0.659) and contains hundreds of galaxies. At left, a distinctive blue arc is actually composed of three separate images of a more distant background galaxy called SGAS J111020.0+645950.8. This background galaxy has been magnified, distorted, and multiply imaged by the gravity of the galaxy cluster in a process known as gravitational lensing .