Telescope: Unitron 155 4” f/15 refractor, Atlas EQ-G
Camera: Canon EOS Ra full frame DSLR
Filter: 2” GSO IR Cut Filter
Guide scope: Orion 50mm Guidescope, ASI120MM, PHD, Dithered every 4 subs
Exposure: 13x180sec, ISO 800, saved as RAW
Darks: Internal (Long Exposure Noise Reduction)
Flats: 32×1/80s tee shirt flats taken at dusk
Average Light Pollution: Bortle 8, poor transparency, haze
Lensed Sky Quality Meter: 18.4 mag/arc-sec^2
Stacking: Mean with a 1-sigma clip
White Balance: Nebulosity Automatic
Software: Backyard EOS, Deepsky Stacker, Nebulosity, Photoshop
M27, the Dumbbell nebula, is an expanding shell of gas that was ejected from a sun-like star as it exhausted its hydrogen fuel. Swollen into a red giant, the star shed its outer shell while its core collapsed into a white dwarf. Fierce UV radiation from the collapsed core sets the surrounds gas aglow with the blue/green light of doubly ionized oxygen. The diameter of the nebula is about 1 light-year with an estimated age of 9,800 years. Located between Sagitta and Cygnus, M27 is fairly easy to find with a small telescope. Visually, it shows two lobes connected by a neck of nebulosity, giving the nebula its characteristic dumbbell shape.
M27 is currently a morning object and is high in the east at dawn.
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