The Shapes of Galaxies
Galaxies have been divided into three basic shapes: elliptical,
spiral, and irregular. Elliptical galaxies appear smooth and featureless.
They can be baseball-shaped to football-shaped. Spiral galaxies are
pinwheel-shaped disks with two or more “arms” winding out from a
central bulge. These arms vary from tight spirals to very loose, bumpy
spirals. Irregular galaxies don’t have arms or a uniform appearance.
Their stars and gas clouds are scattered in random patches.