Using the NASA/ESA Hubble Space Telescope, astronomers have uncovered a cluster of galaxies in the initial stages of development, making it the most distant such grouping ever observed in the early Universe.

In a sky survey made in near-infrared light Hubble has spotted five galaxies clustered together. They are so distant that their light has taken 13.1 billion years to reach us. These galaxies are among the brightest galaxies at that early stage of the Universe’s history. They are also very young: we are seeing them just 600 million years after the Universe’s birth in the Big Bang.

via Hubble Pinpoints Furthest Protocluster of Galaxies Ever Seen.