M20, Trifid Nebula

The Trifid Nebula is a bright nebula in Sagittarius, just 2 degrees or so above the Lagoon Nebula.  This nebula is quite colorful, and consists of 3 distinct types of nebulocity - the red part is an emission nebula, the blue is reflection nebulocity, and the dark lanes consist of dark nebulocity.

This is the full-frame image, on the same scale as the Lagoon posted earlier.  As you can see, the red portion is emission nebulocity, the blue is reflection nebulocity, and the dark lanes accounts for the dark nebulocity.  Again, being this object is near the heart of the Milky Way, the star field is quite rich.

This is a cropped version, again, processed differently than the above...