NASA || A Flight Through the CANDELS Ultra Deep Survey

galaxies has travelled for billions of years across space, the images show the galaxies as they appeared billions of years ago. In addition, the expansion of space has redshifted the light of these galaxies toward longer wavelengths (i.e., to the red end of the visible-light region and into the infrared-light region). The changes seen in galaxies during the fly-through illustrate the changes in galaxy structure and appearance over billions of years of cosmic history. CANDELS is an acronym for the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey project. One of the largest projects ever done with the Hubble Space Telescope, CANDELS surveyed five fields to study the development of galaxies over time. The CANDELS observations of the UDS field complement ground-based observations from the United Kingdom Infrared Telescope.