This image consists of only 12 exposures made as the object was declining towards the horizon late December 2008. It shows only the "cave element", which is the dim and very diffuse bright nebula on the eastern side of a much larger nebula complex containing emission, reflection, and dark nebulosity, which does not show in this image. The "cave element", which has the appearance of a "hole in the sky", or of the entrance of a deep cave - lends the whole nebula its name.

The object lays approx. 2400 lights years from Earth, is 35 light year across, and has a very low absolute magnitude of 16.