Universe Today - April 28, 2009
A really, really long time ago in a galaxy far away, a massive star exploded. On April 23, 2009, the Swift satellite detected that explosion. This spectacular gamma ray burst was seen 13 billion light years away, with a redshift of 8.2, the highest ever measured. As we hinted yesterday, this object is now the most distant known object, and the burst occurred when the Universe was only 630 million years old, a mere one-twentieth of its current age. This event, called GRB 090423, can tell us much about the early Universe. “We completely smashed the record with this one,” said Edo Berger, a professor at Harvard University and a member of the team that first measured the burst’s origin. “This demonstrates for the first time that massive stars existed in the early Universe.”
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“This was a pretty amazing event,” Berger told Universe Today. “Swift detected this gamma ray burst on April 23 and we immediately followed it up with the Gemini North Telescope in Hawaii, after it was demonstrated it did not have a visible light counterpart. That was the initial hint that this might be a distant object. We observed it in infrared and we found in the different infrared bands that there was a sharp break at a wavelength of about 1.1 microns.”
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