Ace the Earth Science SOL 2026 – Rock Your Way to Success!

Galaxies are grouped by shape, and spiral galaxies have a flat, rotating disk with winding arms. The Milky Way fits this pattern: we live in a disk that contains spiral arms and a central bulge, and many models show a bar running through the center. This combination of a disk with arms and a bulge is what places our galaxy in the spiral category (specifically a barred spiral). Elliptical galaxies are more rounded and smooth with little gas, irregulars lack a defined shape, and lenticulars have disks but no prominent spiral arms. The Milky Way’s visible structure includes those arms, so it’s best described as a spiral galaxy.