Hi! Can someone illuminate why there are gravitational tendency in larger scale to form disks (galaxies, solar systems, accretion disks) whereas all smaller scale bodies (planets etc.) are spherical? What about the spherical halos in the galaxies, is just "unorganized matter" which will "settle" in time and be part of the galaxy disk? How about the universe then? If it is not disk like or spherical, does it mean that universe is not rotating as a whole? Or is it because the universe is not in its final shape yet if there is one final shape ever to be? Thanks!