AzTEC-3

AzTEC-3 (aka AzTEC J100020.54+023509.3 or COSMOS AzTEC-3) is a high-redshift starburst galaxy with an extremely high star formation rate, discovered in 2008 at z = 5.3 by AzTEC, a bolometer-array camera, at the time installed on the James Clerk Maxwell Telescope (JCMT). The galaxy is surrounded by a group of galaxies forming stars at high-but-more-usual rates and shows signs of a recent galaxy merger. It lends evidence to the theory that galaxies grew through mergers and through the effect of mergers on their gas. Its redshift (using techniques more advanced than Hubble's law) places it at a distance of roughly 12.6 Gly, about a billion years after the Big Bang. The grouped galaxies are considered a proto-cluster and the most distant galaxy group or cluster. The cluster is often referred to by the galaxy's name, e.g., the cluster AzTEC-3 or the AzTEC-3 cluster.