Short orbital-period binary star detected at the heart of the planetary nebula M 3-1
(PHYSorg.com Space & Earth)

European astronomers have discovered a new binary star at the center of the planetary nebula M 3-1. The newly found binary has an extraordinary short orbital period of slightly more than three hours, which makes it one of the shortest orbital-period binary central stars known to date. The detection is detailed in a paper published July 30 on arXiv.org.