[Kamog]

I don't understand galaxies. Especially elliptical ones. I can sort of see how a spiral galaxy works, it rotates around so the spiral arms orbit around the center and the rotation and the gravitational pull towards the center balance each other out. So the galaxy doesn't collapse or fly apart.

So why doesn't an elliptical galaxy collapse under its own gravity? If it's spinning, that will stop it from collapsing in the plane of rotation but not at right angles to the rotation.

Also, I wonder how a barred spiral galaxy can form. What happened when the galaxy was forming? The bars full of stars extended outwards from the middle, straight, in opposite directions, and then after the bars grew to a certain length, the whole galaxy started to rotate so that the arms bent into a spiral? How can that happen, I just don't understand!