How to make a massive star

摘要

Two competing theories have been applied to the formation of high-mass stars. Observations of two stellar systems now suggest that the accretion model has a weightier claim than its rival merger model. How do high-mass stars form? Through accretion ? the gravitational collapse of a dense cloud of gas and dust — as do better-understood stars of lower mass like the Sun? Or do they form through the collision or merging of smaller stars? Two papers in this issue find evidence for dense disks of dust and gas around high-mass stars, adding to the mounting evidence for the first of the two options.