The European Space Agency's Faint Object Camera on board NASA's Hubble Space Telescope has provided astronomers with the most detailed image ever taken of the gravitational lens G2237 + 0305 — sometimes referred to as the Einstein Cross. The photograph shows four images of a very distant quasar which has been multiple-imaged by a relatively nearby galaxy acting as a gravitational lens. The angular separation between the upper and lower images is 1.6 arcseconds.
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Description from other version: An Einstein Cross reveals the presence of a huge gravitational lens in the distant reaches of the universe. Astronomers discovered this gravitational lens in 1985 using survey maps of the sky obtained with the Hubble Space Telescope (HST). The bright object at the center of the image is a distant galaxy. The four bright objects surrounding it are actually multiple images of a single quasar that lies far beyond the galaxy. The lens was named the Einstein Cross in honor of Albert Einstein, whose relativity theory predicted the phenomena decades before the first gravitational lens was observed in 1979.