The Snake Nebula - Barnard 72

In 1919, the American astronomer Edward Emerson Barnard compiled a list of dark nebulae known as the Barnard Catalogue of Dark Markings in the Sky, or the Barnard Catalogue for short. The nebulae listed by Barnard have become known as Barnard objects.

There are a handful of separately numbered Barnard objects within this image. The prominent S—shaped object is Barnard 72, a sinuous dark nebula that snakes out in front of the incredibly dense star fields towards the centre of the Milky Way in the constellation of Ophiuchus. Barnard 68 is the particularly opaque bean-shaped dark absorption nebula or Bok globule (see also the Bok globules in IC 2944), situated at a distance of around 40 light-years.

Dark nebulae such as these are both very cold in their interiors, as well as being sufficiently opaque that the stars behind them cannot be seen in visible wavelengths of light. There’s a great deal of diffuse foreground dust in this image too which results in the apparent overall reddening of the background stars, especially towards the bottom of the frame.

The tiny object at the bottom of this image and slightly to the right is NGC 6369, a planetary nebula also known as the ‘Little Ghost Nebula’. It was purely good fortune that I included this object in this field of view - it was spotted only during processing.