Question

What is the term for a galaxy that is a rotating disk of stars and dust?

Answer 1

spiral galaxy

A spiral galaxy is a rotating disk of stars and dust. In the center is a dense bulge of material. Several spiral arms come out from the center. Spiral galaxies have lots of gas and dust and many young stars. The image below   Figure below   shows a spiral galaxy from the side. You can see the disk and central bulge.