September 10, 2008 - ScienceDaily
A flash of light that blinded even small telescopes six months ago was the brightest astronomical explosion ever observed - visible to the naked eye despite originating halfway across the universe.
The gamma-ray burst, catalogued as GRB 080319B, was the result of a massive star's explosion 7.5 billion years ago that sent a pencil-beam of intense light on a direct collision course for Earth. It is the only known gamma-ray burst to have had a visible component bright enough to see with the naked eye.
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The Katzman Automatic Imaging Telescope (KAIT) at Lick Observatory also followed the fading afterglow of the burst, as did the Gemini South telescope in Chile. Bloom and his colleagues combined these observations with Swift data and Pi of the Sky images to complete their analysis.
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