Hubble Looks Through Cosmic Zoom Lens (6 cropped images)

A selection of cropped images from a NASA/ESA Hubble Space Telescope Advanced Camera for Surveys view of one of the most massive galaxy clusters known, called Abell 1689. These close-ups show 'lensed' images of background galaxies that have been brightened and smeared by the gravitational bending of light by the foreground cluster.

The yellow-white objects are the cluster galaxies located 2.2 billion light-years away. The blue arcs are the distorted images of background galaxies located billions of light-years farther away than Abell 1689.

The distribution of both 'normal' and dark matter, and the alignment of the background galaxies determine the amount of distortion. In a perfectly aligned gravitational lens the background object would be smeared into an 'Einstein ring.' Instead, there are numerous ring sections or arcs corresponding to individual galaxies.