Record-breaking X-ray blast briefly blinds space observatory

A blast of the brightest X-rays ever detected from beyond our Milky Way galaxy's neighborhood temporarily blinded the X-ray eye on NASA's Swift space observatory earlier this summer, astronomers now report. The X-rays traveled through space for 5-billion years before slamming into and overwhelming Swift's X-ray Telescope on 21 June. The blindingly bright blast came from a gamma-ray burst, a violent eruption of energy from the explosion of a massive star morphing into a new black hole. "This gamma-ray burst is by far the brightest light source ever seen in X-ray wavelengths at cosmological distances," said David Burrows, senior scientist and professor of astronomy and astrophysics at Penn State University and the lead scientist for Swift's X-ray Telescope (XRT).

Although the Swift satellite was designed specifically to study gamma-ray bursts, the instrument was not designed to handle an X-ray blast this bright. "The intensity of these X-rays was unexpected and unprecedented" said Neil Gehrels, Swift's principal investigator at NASA's Goddard Space Flight Center. He said the burst, named GRB 100621A, is the brightest X-ray source that Swift has detected since the observatory began X-ray observation in early 2005. "Just when we were beginning to think that we had seen everything that gamma-ray bursts could throw at us, this burst came along to challenge our assumptions about how powerful their X-ray emissions can be," Gehrels said.