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. Gemini Observatory/NSF/AURA, D. Fox and A. Cucchiara (Penn State University) and E. Berger (Harvard University)From Scientific American:
A stellar explosion spotted in April took place 13 billion years ago.
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.
NASA's Swift Gamma-Ray Burst spacecraft spotted the flash signaling a massive stellar explosion on April 23. The explosion was officially designated GRB 090423, after its type (a gamma-ray burst) and date of detection; the space agency quickly announced it as the new record holder for cosmic distance. Now, two papers in the October 29 Nature present detailed analyses of the burst and afterglow, confirming the initial distance assessments and providing a few clues as to conditions in the early universe.
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