Sh2-223 & Sh2-224 in Auriga

[gorann]

These two quite faint objects from the Sharpless catalogue were once thought to both be supernova remants (planetary nebulae) but now only Sh2-224 (the one to the left) is recognized as a supernova remnant, with the typical blue Oiii mixed with Ha emission. Sh2-223 does not contain any detecatble (Oiii) and is now thought to be a Ha emitting nebula energized by the star BD+41 1144. For those that want to read more about thes objects a good start is, as allways, to read Gary Imm's description of his rendention of these objects (https://www.astrobin.com/380492/F/), where also BD+41 1144 is pointed out.

To me Sh2-224 looks like some kind of flying creature. or rather gliding, coming in for landing on Sh2-223.

Data collected 10 Nov 2021 with my dual RASA8 rig on a Mesu200. ASI2600MC (gain 100, offset 30, -10°C) with IDAS NBZ filer (Ha and Oiii dual band). 110 x 5 min, so 9.2 hours. Processed in PI and PS. After some initial stretches I made a starless image using the Star Xterminator filter before stars were brought back. This greatly helped to suppress the starfield that otherwise can easily overwhelm these quite faint nebulae.

Cheers, Göran