About three times a second, a 10,000-year-old stellar corpse sweeps a beam of gamma-rays toward Earth. This object, known as a pulsar, is the first one known to blink only in gamma rays, and was discovered by the Large Area Telescope (LAT) onboard NASA's "Enrico Fermi" Gamma-ray Space Telescope, a collaboration with the U.S. Department of Energy (DOE) and international partners. The gamma-ray-only...