Gravitational lensing. Hubble Space Telescope view of lensed galaxies (arcs) seen through the galaxy cluster Abell 1689. Abell 1689 lies around 2.2 billion light years from Earth. It is so massive that it bends the path of the light from galaxies even further away behind it, acting like an enormous lens in space. This means it can be used to study more distant galaxies that it would be possible to observe without the cluster. The fine arcs are the distorted images of galaxies from up to 13 billion light years away, seen as they were when the universe was less than a billion years old.