Sharpless 105 Sh2-105 covers the famous Crescent Nebula region in Cygnuss. Often considered to be a planetary nebula, Sh2-105 is actually caused by the steller wind coming from WR 136 the Wolf-Rayet star in the middle. Sharpless 105 is around 5000 light years away, based on the apparent size this makes it about 20 light years across. Rather amusingly this is also known as the "Euro Sign Nebula" due to the visual apperance in telescopes.
Sh2-105 is deep within a lot of Ha emission fluff in the cygnus region which shows up nicely in deeper images.
The images here are mostly Ha narrowband - and do not show the faint OIII outer fluff. The Crescent nebula fits very nicely in my field of view and generally gets a lot of attention very early in the season when I'm tuning equipment.
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