This is a small portion of a much larger nebula in the constellation of Cygnus. The Pelican is much studied because it has a particularly active mix of star formation and evolving gas clouds. The light from young energetic stars is slowly transforming cold gas to hot and causing an ionization front gradually to advance outward. Particularly dense filaments of cold gas are seen to still remain. For a wide angle view that includes this odd dark cylindrical cloud near the right center click here. This image was taken June 26-28, 2010. It is composed of 5 hours of exposure through a hydrogen-alpha filter, and 90 minutes through red, blue and green filters. Seeing conditions were fair, with temperatures in the low 90s.