Most Milky Way Runaway Stars Aren’t Born in Binaries, New Survey Finds

Spanish researchers using Gaia astrometry and the IACOB spectroscopic database analyzed 214 O-type runaway stars and found that most did not originate as binary companions; the fastest runaways tend to be single, while faster rotators are linked to binary-supernova ejections, indicating multiple ejection mechanisms. The study also identified 12 runaway binaries, including three X-ray binaries with neutron stars or black holes, underscoring complex pathways for how these stars leave their birthplaces and influence galactic evolution.