Description:
The Cocoon Nebula (Sh2-125 / IC 5146) is a star-forming region in Cygnus, about 4,000 light-years away.
At its center, a young massive star lights up surrounding hydrogen gas, creating a glowing emission nebula wrapped in dark dust. Spanning roughly 15 light-years, it combines red hydrogen glow, blue reflection light, and obscuring dust lanes.
The nebula sits at the end of the dark filament Barnard 168, making it appear as a glowing cocoon in space. It is both a beautiful deep-sky object and an important site for studying the birth of stars.