Nightscapes & Deep Sky Colors
Astrophotography © Brian A. Morganti
Cocoon Nebula Sh2-125
with Open Cluster IC 5146 & Dark Nebula B168
The Cocoon Nebula, which includes both emission and reflection nebulosity, is a stellar nursery with its delicate fabric of glowing hydrogen torn asunder by the solar wind of newborn stars. Beyond the glow of the hydrogen, the surrounding interstellar dust begins to dominate. At the edge of the red emission nebula, this dust reflects pale blue light from nearby stars. Farther away, the dust fades, and instead blocks the light of the background stars. The nebula is about 12 arc-minutes across, but in actual size is about 15 light-years across.
The star cluster IC 5146 is sparse and only contains about 20 stars, the brightest of which is about magnitude 9.6 near the center of the cluster and nebula. This cluster is about 4000 light-years away.
The dark nebula B168 (Barnard) is visible in binoculars and is rather interesting amidst the rich star fields in Cygnus. This dark nebula surrounds the cluster-nebula and then extends westward forming the appearance of a trail behind the Cocoon.