... Credit Copyright: NASA , ESA , G. Illingworth ( UCO/Lick UCSC ), R. Bouwens ( UCO/Lick Leiden U. ), the HUDF09 Team Explanation: When did galaxies form? To help find out, the deepest near-infrared image of the sky ever has been taken of the same field as the optical-light Hubble Ultra Deep Field (HUDF) in 2004. ... These galaxies therefore likely existed when the universe was only a few percent of its present age , and may well be members of the first class of galaxies . ...