Astronomy.com - April 28, 2009
The Swift satellite has found a gamma-ray burst from a star that died when the universe was 640 million years old, or less than 5 percent of its present age. The event, called GRB 090423, is the most distant cosmic explosion ever seen and gives astronomers an insight into the early universe. The international team, led by United Kingdom and United States astronomers, announced the discovery today.
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Shortly after, Fox led an effort to obtain infrared images of the afterglow using the Gemini North Telescope on Mauna Kea. The source appeared in longer-wavelength images, but was absent in an image taken at the shortest wavelength (1 micron). The drop-out corresponded to a burst distance of about 13 billion light-years.
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