M-82 Star Cluster with the Shroud image over it, see how it lines up!

In the infrared light, M82 is the brightest galaxy so far know. It exhibits an infrared excess – much brighter at infrared wavelengths than in the visible part of the spectrum. "Our results provide a set of constraints for detailed starburst modeling, which we present in a companion paper. We find that purely foreground extinction cannot reproduce the global relative intensities of H recombination lines from optical to radio wavelengths." says N. M. Förster Schreiber (et al), "The excitation of the ionized gas indicates an average effective temperature for the OB stars of 37,400 K, with little spatial variation across the starburst regions. We find that a random distribution of closely packed gas clouds and ionizing clusters and an ionization parameter of 10-2.3 represent well the star-forming regions on spatial scales ranging from a few tens to a few hundreds of parsecs. From detailed population synthesis and the mass-to-K-light ratio, we conclude that the near-infrared continuum emission across the starburst regions is dominated by red supergiants with average effective temperatures ranging from 3600 to 4500 K and roughly solar metallicity. Our data rule out significant contributions from older, metal-rich giants in the central few tens of parsecs of M82."

For more information on M82, and the rest of the above article, see http://www.universetoday.com/guide-to-space/messier-objects/messier-82/