In a recent American Scientists article about pro-stars and star
formation I saw a diagram that is pretty common in those sorts of
discussions which I still don't understand fully. Can anyone give me
an intuitive and/or conceptual feel for why when gas undergoes
gravitational collapse it should form a disk (thought to be the
origin of planets) at the rotational equator and jets at the poles
with material moving OUTWARD?
I can see that orbits in planes parallel to the equatorial are
unstable but- so why aren't stars flat rotating disks? What am I
missing here?