A massive cluster of galaxies known as Abell S1063 acts as a gravitational lens, distorting the view of galaxies beyond the cluster. These distortions show up as arcs around the cluster, which is at the center of this Hubble Space Telescope image.  Abell S1063 is about four billion light-years from Earth, and contains between 50 and 450 galaxies. Their total mass is roughly 100 times the mass of our home galaxy, the Milky Way. [NASA/ESA/J. Lotz (STScI)]