Enormous Galaxy Cluster Seen Distorting Space-Time Fabric

Bright arcs can be seen smeared around the heart of the enormous galaxy cluster Abell S1077 in this image taken by the Hubble space telescope. These arcs are actually stretched images of distant galaxies distorted by the cluster's huge gravitational field.

Galaxy clusters are large groups of sometimes thousands of galaxies, each hosting billions of stars. They are the largest gravitationally bound structures in the Universe, only dwarfed by the superclusters that they are part of.

The amount of matter condensed in such groupings is so high that their gravity is enough to warp even the fabric of space-time, distorting the path that light takes when it travels through the cluster. This strange effect is called gravitational lensing, and it can function like a giant magnifying glass

The bizarre phenomenon of gravitational lensing is a consequence of Albert Einstein's general theory of relativity, which says that the huge mass of the galaxy cluster bends the fabric of the Universe, and the light from one of the distant galaxies will then travel along this bend in the fabric. In addition to making some objects appear bigger and brighter, gravitational lensing can produce multiple images of distant galaxies and stretch them into strange arcs, which can be seen in the picture.

Astronomers use the effects of gravitational lensing to peer far back in time and space to see the furthest objects located in the early Universe.

One of the record holders is galaxy MACS0647-JD, whose light was magnified by galaxy cluster MACS J0647+7015 and has been travelling for 13.3 billion years to reach Earth.