B - 15 µm map of M51/NGC 5195.
North is up. Features that are bright at 15µm or dark in B are bright in this image. Brightness is plotted proprotionally to the logarithim of the intensity of the source in order to reveal faint features. (Click here for full image, x2)

This image is discussed in the Astrophysical Journal Letter;

"Macromolecules, Very Small Grains, and Large Dust Particles in the Whirlpool Galaxy M51 and Its Companion: A Unified View", by David L. Block et al.

An ISO image of M51 and more information concerning this source can be found here.