May 26, 2011 - MSNBC.com
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The explosion was observed by NASA’s Swift satellite in April 2009, and it was named GRB 090429B. Though the initial blast lasted only about 10 seconds, the event left a fainter afterglow that was visible in the sky for days. Researchers observed this afterglow with the Gemini North telescope on Mauna Kea in Hawaii.
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