The Hubble Deep Field . ... Credit Copyright: R. Williams, The HDF Team ( STScI ), NASA Explanation: Galaxies like colorful pieces of candy fill the Hubble Deep Field - one of humanity's most distant optical views of the Universe . The dimmest, some as faint as 30th magnitude (about four billion times fainter than stars visible to the unaided eye), are very distant galaxies and represent what the Universe looked like in the extreme past, perhaps less than one billion years after the Big Bang . ...