The Cocoon Nebula, IC 5146, a reflection and emission nebula in Cygnus, illuminated by the central hot star.
The nebula is surrounded by a dense molecular cloud which expands outwards in the iconic tail-shaped dust lanes, forming several magnificent figures.
Diffuse Ha emission dominates the background.
Image is the result of a two-panels mosaic for a total 30 hours integration time in HaLRGB
High resolution here