A little bit of spin goes a long way…
Galactic shear and
turbulence give every core a little spin
(once round in 10 million years). But they get a lot smaller, and the spin goes up – to orbital!
It is for this reason that
we believe there are many planetary systems – it is part and parcel of the star formation process to make a disk. Typical Galactic spin makes disks about the size of our Solar System…