By no means all galaxies are spiral in shape. This illustration - of NGC 5253 in Centaurus - shows another less common galactic form, the irregular galaxy.
Vast accumulations of stellar material, typically containing several million individual stars. They range in appearance from the irregular, through the elliptical, to delicate and elaborate spirals.
A typical spiral galaxy, adrift in a still and starless void. This is M109 in a Ursa Major, a galaxy fairly similar to our own Milky Way Galaxy. Galaxies like this can be tens or hundreds of thousands of light yearsacross, and carry thousands of millions of stars. Imagery provided by Aladin sky atlas
