October 28, 2009 - Scientific American
A violent explosion picked up by a NASA satellite earlier this year is the oldest object ever seen by astronomers, its light having been emitted some 13 billion years ago. At that time the universe was roughly 5 percent of its present age and the big bang was a fairly recent occurrence, having taken place just 600 million years earlier.
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[Image caption: A false-color image from the Gemini North Telescope in Hawaii shows the afterglow of GRB 090423 [circled], the most distant astronomical event yet observed.]