Cosmic Magnifying Glass
This giant magnifying glass-a massive cluster of galaxies called Abell 2218-resides in the constellation Draco, some 2 billion light-years from Earth. The cluster is so massive that its powerful gravitational field deflects light rays passing through it, much as an optical lens bends light to form an image. The phenomenon, called gravitational lensing, magnifies, brightens and distorts images from objects in the remote universe, and acts as a "zoom lens" for studying objects otherwise beyond reach. The "arcs" in the image are actually distorted galaxies five to 10 times farther away than the lensing cluster. Hubble has been watching the cluster since 1994 and took this latest shot in January.
Photo by NASA, Andrew Fruchter (STScI) and the ERO team (STScI, ST-ECF).
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