Posted: Thu, Dec 13, 2012, 7:17 AM ET (1217 GMT)
Astronomers have found a population of galaxies more than 13 billion years old in a new "deep field" image set from the Hubble Space Telescope. The galaxies, found in Hubble's Ultra Deep Field 2012 (UDF12) near-infrared images, date back to between 350 and 600 million years after the Big Bang. Astronomers report that the images show the population of galaxies gradually decreases going back in time to about 450 millions years after the Big Bang, supporting models where "reionization," a reheating of cold hydrogen gas in the universe, took place gradually over the course of several hundred million years as the first galaxies formed. Astronomers used Hubble to take the UDF12 images with the telescope's Wide Field Camera 3 during August and September.

Related Links:

•  SPACE.com article
•  New Scientist article
•  AP article
•  Reuters article
•  NASA press release