How tight pairs of massive stars are born
In a star cluster, like on a crowded dance floor, massive stars rarely stay single. More often they whirl in pairs or triples, and the distance between them can be less than from Earth to the Sun. But how do they manage to get so close to each other?
Simulations showed: it's all about the disk of gas and dust that envelops the pair. This disk, like a drain funnel, swirls the stars and slowly pulls them inward.