Hubble Ultra Deep Field 2012

In 2012, astronomers used the Hubble Space Telescope to revisit the Hubble Ultra Deep Field, peering even deeper than before at the near-infrared light of the cosmos. Astronomers use infrared light to study the distant universe because the expansion of space stretches wavelengths of light toward the red end of the electromagnetic spectrum, a phenomenon called "redshift." The result was the Hubble Ultra Deep Field 2012. The observations uncovered a previously unseen population of seven primitive galaxies that formed more than 13 billion years ago, when the universe was less than 3 percent of its present age, or about 450 million years after the Big Bang.