Trifid Nebula

This is the Trifid Nebula (Messier 20), located in Sagittarius. I really like the contrast between the red and blue.The red color comes from gas that is ionized by the stars within the nebula. (This ionization effect is basically the same effect that makes neon and fluorescent lights glow.) The blue is from light that is being reflected off of gas and dust. Trifid means "divided into three lobes," which refers to the dark dust lanes that divide the red portion of the nebula.

Open cluster Messier 21 is on the left in this image:

Messier 20 and Messier 21, E-200, 11x120

Val Ricks and I each imaged the Trifid Nebula at about the same time, so we decided to combine our image data into a single image. Below is my version of the result. Note the diffraction spikes on the star in the lower-left!

Trifid Nebula Collaboration