The highest-energy initial emissions ever seen.
If gas can move at 99.9999 percent of the speed of light then why not heavier objects?
February 20, 2009: The first gamma-ray burst to be seen in high-resolution from NASA's Fermi Gamma-ray Space Telescope is one for the record books. The blast had the greatest total energy, the fastest motions and the highest-energy initial emissions ever seen.
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Within the jet of this burst, gas bullets must have moved at least 99.9999 percent the speed of light.