noao0111 — Science Release
Galaxy Cluster Found Using Gravitational Distortion, Suggests Independent Test of Accelerating Universe
14 August 2001: Astronomers using the National Science Foundation's Blanco Telescope in Chile have used the distorting effects of a weak gravitational lens to discover and locate a dim cluster of at least 15 galaxies at a significant distance from Earth, using only the mass properties of the cluster, not its visible light.