The spiral galaxy M31 is the nearest example of this kind of galaxy. It is inclined to our line of sight so that we can see structure in the spiral arms as well as the central bulge. Observations of galaxies like these can help us determine the structure of our own Galaxy, the Milky Way.

This image is a colour composite of images taken at different wavelengths in the infra-red part of the spectrum. Red, green and blue correspond to 100, 60 and 25 micons respectively.

Image credit: IRAS