Start the music! With “Children of the Night” playing in my head, I shot this faint target last night.
Sh2-173 is an extremely faint emission nebula rich in ionized Hydrogen with a diameter of 77 light-years. It is part of the Perseus arm of our Milky Way Galaxy. Its shape and dark dust clouds bear a resemblance to the mask worn by the Phantom of the Opera in the Broadway musical or the film starring Lon Chaney. Hence it is commonly referred to as the Phantom of the Opera Nebula.
Distance:
Sh2-173 is about 8800 light-years (51 quadrillion miles) from Earth in the constellation Cassiopeia.
Imaging:
I knew this would be a tough, dim target so I shot 21x600s @ 100 gain. Three of those were rejects, due to clouds, so I stacked only 18 shots @ 10 minutes each, and cailbrated with 20 @ biases, 20 @ darks, 20 @ flats, and 20 @ dark flats
Equipment:
- Telescope: SVBony SV503 80ED 560mm, an f/7 Doublet Refractor telescope with a 0.8 Reducer/Flattener to reduce the focal length to 448mm and aperture to f/5.6
- Mount: SkyWatcher HEQ5 Pro
- Camera: ZWO ASI2600 MC Pro
- Filter: L-Extreme, Bortle-6 skies
- Guiding: ZWO ASI120mm Mini Monochrome Guide Camera with the ZWO 30mm f/4 Guide Scope
- Automation: ZWO ASIAir Mini
Still don’t see it? Turn the image slightly counter-clockwise.
