Astronomers, including a team member from NASA's Jet Propulsion Laboratory in Pasadena, Calif., have detected the first population of radio bursts known to originate from galaxies beyond our own Milky Way. The sources of the light bursts are unknown, but cataclysmic events, such as merging or exploding stars, are likely the triggers. A radio burst is a quick surge of light from a point on the sky, made up of longer wavelengths in the radio portion of the light spectrum. A single radio burst was detected about six years ago, but researchers were unclear about whether it came from within or beyond our galaxy. The new radio-burst detections -- four in total -- are from billions of light-years away, erasing any doubt that the phenomenon is real. The discovery, described in the July 4 issue of the journal Science, comes from an international team that used the Parkes Observatory in Australia.