20% of all massive stars in the Milky Way have unusually high velocities, the origin of which has puzzled astronomers for half a century. A new model replicates the key characteristics of these OB runaways, and explains their presence  around young star clusters. The  model reproduces the high proportion and the distributions in mass and velocity of runaways in the Milky Way, if the majority of massive stars are born in small compact star clusters.

Source: Science Magazine