Most Surprising Explosion
Caltech and Penn State astronomers have found an explosive burst of gamma rays that seem to come from nowhere. Gamma rays usually follow the death of a massive star but these bursts were 88,000 light-years from the nearest galaxy.
Image: NASA, Holland Ford (Johns Hopkins University), Garth Illingworth (UC Santa Cruz/LO), Mark Clampin (Space Telescope Science Institute), George Hartig (STScI), the ACS Science Team, and ESA