-
- The Andromeda galaxy is one of the most beautiful examples of a spiral galaxy in the night sky.
-
- The Sombrero galaxy illustrates both a spiral disk and a halo of stars.
-
- The spiral structure of the Pinwheel Galaxy.
-
- A model for explaining how spiral arms form in a galaxy.
-
- Spiral arms are like traffic jams, which persist even when cars are continuously moving in the back and out the front.