This photo, called the eXtreme Deep Field (XDF) was created by combining 10 years of NASA Hubble Space Telescope photographs taken of a patch of sky at the center of the original Hubble Ultra Deep Field, according to NASA.
It contains about 5,500 galaxies even within its smaller field of view, according to NASA, and the faintest galaxies are one ten-billionth the brightness of what the human eye can see. The universe is 13.7 billion years old, and the XDF reveals galaxies that span back 13.2 billion years in time.
The first such deep view of space was the Hubble Ultra Deep Field -- an image of a small area of space in the constellation Fornax, created using Hubble Space Telescope data from 2003 and 2004. By collecting faint light over many hours of observation, it revealed thousands of galaxies, both nearby and very distant, making it the deepest image of the universe ever taken at that time.
Photo credit: NASA; ESA; G. Illingworth, D. Magee, and P. Oesch, University of California, Santa Cruz; R. Bouwens, Leiden University; and the HUDF09 Team