Spiral Galaxy

Spiral galaxies are characterized by their disk-like shape, winding spiral arms, densely populated central bulge, and sparsely populated halo. Stars in the spiral arms are younger and bluer on average, while stars in the bulge and halo tend to be older and redder. Spirals come in two varieties: "grand-design", and "flocculent". Grand-design spirals have a small number of well-defined arms which wind outward from the central bulge, while flocculent spirals have many chaotic armlets which generate randomly throughout the galactic disk. Flocculent spirals may also posses star clusters which vary in scale and frequency from galaxy to galaxy.

Spiral galaxies are the most complex galaxy morphology and can vary greatly from each other in size and shape. They are relatively common compared to other morphologies when playing with the "default" verse preset, and tend to generate in galaxy clusters, but can also generate in the voids between clusters.