LBN 438 is a dusty nebula located in the Lacerta constellation which is also known as the sand worm (from the Dune science fiction series) or the shark nebula. It doesn’t appear very often on SGL, probably because it is so faint !
It is illuminated by interstellar radiation known as Extended Red Emission (ERE). ERE is a relatively recent discovery (1975) and is a photo-luminescence process whereby hydrogenated amorphous carbon is illuminated by interstellar photons in the 500 to 1000nm spectral range. Although the nebula also contains ionized hydrogen, it only emits a relatively weak Ha signal, so I decided to only use broadband filters to acquire the target.
The LRGB image shown below was captured with my Esprit 150 and represents just over 13 hours integration time.
At the top of nebula is a reddish glow, which I presume is due to ERE. The nebula is surrounded by very bright blue stars which can detract from the relatively faint nebula, so these have been stretched much less than the rest of the image and then blended back into the main image. If you look closely at the background you will also be able to see various small background galaxies (eg middle left).