New theory points to 'zombie vortices' as key step in star formation

A new theory by fluid dynamics experts at the University of California, Berkeley, shows how "zombie vortices" help lead to the birth of a new star.

Reporting today (Tuesday, Aug. 20) in the journal Physical Review Letters, a team led by computational physicist Philip Marcus shows how variations in gas density lead to instability, which then generates the whirlpool-like vortices needed for stars to form.

Astronomers accept that in the first steps of a new star's birth, dense clouds of gas collapse into clumps that, with the aid of angular momentum, spin into one or more Frisbee-like disks where a protostar starts to form. But for the protostar to grow bigger, the spinning disk needs to lose some of its angular momentum so that the gas can slow down and spiral inward onto the protostar. Once the protostar gains enough mass, it can kick off nuclear fusion.