Pan across CLASS B1608+656

Hubble's images might look flat, but this one actually has a remarkable depth of field that lets us see more than halfway to the edge of the observable Universe.

Most of the galaxies visible here are members of a huge cluster called CLASS B1608+656, which lies about five billion light-years away. But the field also contains other objects, both significantly closer and far more distant, including quasar QSO-160913+653228 which is so distant its light has taken nine billion years to reach us, two thirds of the time that has elapsed since the Big Bang.