This is the Pinwheel Galaxy, M101, in a wide-ish field LRGB composite. Usually one would image this beauty at a slightly larger focal length, but this wider field puts the galaxy into a nice context. M101 is a large galaxy, quite comparable to the Milky Way. With a diameter of 170,000 light-years it is about equal in size. It has a disk mass of around 100 billion solar masses, along with a central bulge of about 3 billion solar masses.

The image is composed of 24 x 900sec luminance and (16,20,20) x 600sec RGB frames taken at the Deep Sky West Observatory. Standard processing with modest color enhancement.