IC 5146, the Cocoon Nebula, is involved with open star cluster Collinder 470, and lies at the end of an interesting dark nebulae, Barnard 168, in Cygnus.

The nebula includes reflection nebulosity and emission nebulosity and is bisected by several dark lanes.

The cluster, which shines at magnitude 7.2, is not very rich, containing only 20 stars, the brightest of which is magnitude 9.6 at the center of the cluster and nebula.

IC 5146 is believed to be 4,000 light-years distant. At that distance, its apparent size of 12 x 10 arcminutes would correspond to a true size of 14 light-years in space.

IC 5146 was discovered by Thomas Espin in 1899.

North is to the top in the above image.

IC 5146 Catalogs: IC 5146, LBN 424 Common Name: Cocoon Nebula Object Type: Emission Nebula and Cluster Magnitude: 7.2v Size: 10' x 10' Constellation: Cygnus Image Field Centered At: RA: 21h 53m 27s Dec: +47° 15' 41"