 You'll remember the Einstein ring we saw around ESO325-G004 in our segment on local superclusters. The ring was the image of a more distant galaxy. The arc shape was created by the bending of the background galaxy's light by the gravity of the massive foreground galaxy. The process is called gravitational lensing because the mass between us and the background galaxy behaves just like an optical lens. This same light bending leads to the warping of light from distant galaxies as the light encounters supermassive galaxies on their path to us. Here's a clip that shows how this lensing works on a grand scale. A distant galaxy would be seen here on Earth directly if there were no intervening massive cluster to bend the light. But with such a cluster, the light from the distant galaxy gets bent into rings and arcs that continue on to the Earth. This is Abel 1689, 2.2 billion light years away. It's one of the most massive galaxy clusters known. Its gravity acts like a 2 million light year wide lens in space. Here again we see how the gravitational field surrounding this massive cluster of galaxies acts as a natural lens in space to brighten and magnify the light coming from very distant background galaxies. In this photo, the galaxy is visible twice because its light followed two separate paths around Abel 68 before reaching us. This is a close up look at the brightest distant magnified galaxy in the universe known to date. It is one of the most striking examples of gravitational lensing. In this image, the light from a distant galaxy nearly 10 billion light years away has been warped into a nearly 90 degree arc of light in the galaxy cluster. The galaxy cluster that is bending the light lies 5 billion light years away. And here's another cluster, 5.7 billion light years away. These foreground galaxy clusters are magnifying the light from the faint galaxies that lie far behind the clusters themselves. These faint lensed galaxies are around 12 billion light years away. It's the gravitational lensing that allows us to see that far back in time. Without the magnification, these galaxies would be invisible for us. This Hubble image shows a massive galaxy cluster about 4.6 billion light years away. Along its border, four bright arcs are visible. These are copies of the same distant galaxy nicknamed the Sunburst Arc. It's almost 11 billion light years away. Its light is being lensed into multiple images by strong gravitational lensing. The Sunburst Arc is among the brightest lensed galaxies known, and its image is visible at least 12 times within the four arcs. Here's a closer look at three of them. The lens makes various images from 10 to 30 times brighter. This allows Hubble to view structures as small as 520 light years across. A rare detailed observation for an object that far away.