The other large galaxies are the Andromeda Galaxy, and Messier 33 (the 33rd entry in Charles Messier's catalog of fuzzy things in the sky). Also in the Local Group are a couple dozen dwarf galaxies.
The Triangulum Galaxy, within which NGC 604 sits, is also known as Messier 33 (M33). The gas clouds that fill this star-birthing region are estimated to be around 1,300 light-years across.
The spiral galaxy Messier 33 (M33), also known as the Triangulum Galaxy, is the third-largest member of the Local Group of galaxies, after the Andromeda galaxy (M31) and our own Milky Way.