Sh2-125 is an astronomical catalog designation for the Cocoon Nebula, also known as IC 5146 or Caldwell 19. It is a stellar nursery. It is also a combination emission and reflection nebula in the constellation Cygnus. The nebula is about 4,000 ly away, and the central star that lights it formed about 100,000 years ago.
The nebula gets its “cocoon” shape because the star birth within it has expelled gas and dust. It sits at the eastern end of a long, dark lane of dust. This is the dark nebula Barnard 168 (B168), which appears as a trail behind the glowing cocoon. Based upon the scarcity and dimness of the stars I’d say there’s a lot of dust all around the cocoon.
It is situated in a star-rich region of the Milky Way, which can make it challenging to spot. When viewing Sh2-125, dark nebula Barnard 168 (B168) is an inseparable part of the experience. It forms a dark lane that surrounds the cluster. This lane projects westward, creating the appearance of a trail behind the Cocoon. In short it’s a beautiful celestial object.
This image consists of 130 3 minute exposures calibrated, registered, integrated, and processed in Pix Insight. Subframe acquisition and session automation via APT. Astrobin link for acquisition details and annotated image.
