Astronomers find evidence of the arrival of starlight
A team of astronomers says it has found evidence of the period billions of years ago when starlight first began streaming through the universe.
The findings appear to strengthen the case that telescopes are able to look back far enough in time to glimpse the period when stars and galaxies first formed.
The findings focus on a "fog" or haze that's thought to have pervaded the universe before it was dissipated by light from the first stars, galaxies and other celestial structures.
Scientists believe the universe was created by a huge explosion - the Big Bang - about 13 to 14 billion years ago.
According to findings by the Sloan Digital Sky Survey, the universe later went through the dark period, which ended when it was about 900 million years old.
The Sloan Survey is a project aimed at mapping a section of the sky and recording 200 million celestial objects.
"It took a long time ... for gravity to get its act together and start clumping the gas together" to form stars and galaxies, said Robert Becker, a physics professor at the University of California and researcher at Lawrence Livermore National Laboratory, who led the team that made the "dark ages" finding.
The team made the discovery by examining the farthest object known from Earth - a quasar discovered by the Sloan survey in April that is 14.5 billion light-years away.
The study has been submitted for publication in the Astrophysical Journal Letters.
