Just over one year ago, NASA announced that the most distant galaxy yet found may have been spotted. Just two months later another galaxy took the title of most distant candidate. As astronomers improve techniques to peer further into the universe's past this sort rapid record-setting can be expected for years to come, and today yet another galaxy has actually been confirmed as the most distant.
Astronomers from the University of Texas today announced that they have spotted a galaxy as it existed just 700 million years after the big bang. Though this is older than the galaxies discovered last year, this one is the only one that has had its age confirmed using multiple telescopes. A paper on the galaxy and its discovery will appear tomorrow in the journal Nature.
“We want to study very distant galaxies to learn how galaxies change with time, which helps us understand how the Milky Way came to be,” said Steven Finkelstein, the UT astronomer who lead the discovery team.
The galaxy, dubbed z8_GND_5296, was originally discovered as part of the Hubble space telescope's Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey. The team at UT had chosen 43 of the most distant galaxies from that survey based on their redshift and then used the Keck Observatory in Hawaii to follow up on Hubble's observations. Galaxy z8_GND_5296 was discovered in a region of the sky as another previously most-distant galaxy.
“So we’re learning something about the distant universe,” said Finkelstein. “There are way more regions of very high star formation than we previously thought.…There must be a decent number of them if we happen to find two in the same area of the sky.”
(Image courtesy V. Tilvi/S.L. Finkelstein/C. Papovich/Hubble Heritage Team)