October 2020 - Picture of the Month
LDN 1235 (Shark Nebula) in Cepheus
More dust and reflections in my Picture of the Month as we head to one of my favourite constellations.
Whilst the band of dust that traverses the diagonals of this glorious image culminating at the top left in the Shark nebula (LDN 1235) itself forms the main feature for this month, it's set off beautifully by the two reflection nebulae in their characteristic blue: vdB 149 and vbB 150.
According to my reading LDN 1235 is likely an Extended Red Emission nebula (ERE) which emits between 600 and 800 nm. Given the redness of this and the proximity to that magnitude 6 star I doubt that this faint extended object is a visual target. It's normally the dense background of Milky Way stars that make dark nebulae visible rather than red emitted radiation. LDN 1235 sits well north of the Milky Way.
As for the two reflection nebulae at the top and bottom of this image, the van den Bergh (vdB) catalog lists both with surface brightness of M (moderate), and that makes them a tough visual challenge as well, but possible.
As you can see though these objects make wonderful imaging targets.
James Whinfrey - Website Administrator.