NGC6888 Crescent Nebula



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The Crescent Nebula (also known as NGC 6888, Caldwell 27, Sharpless 105) is an emission nebula in the constellation Cygnus, about 5000 light-years away from Earth. It was discovered by Friedrich Wilhelm Herschel in 1792. It is formed by the fast stellar wind from the Wolf-Rayet star WR 136 (HD 192163) colliding with and energizing the slower moving wind ejected by the star when it became a red giant around 250,000 to 400,000 years ago. The result of the collision is a shell and two shock waves, one moving outward and one moving inward. The inward moving shock wave heats the stellar wind to X-ray-emitting temperatures. [Wiki]


Optic SW ED80 + 0,85 Reducer/Flattener
Camera Atik 383L+
Filters Baader Ha 36mm
Mount NEQ6 with EQASCOM
Guide
SW 70/500 with AlCCD5
Frame center
RA 20:12:11 Dec 38:19:52 J2000
Date
2016/07/17
Site
Backyard, Busto G. Milan, Italy
Exposures Ha 8x900s @-10°C

Integration time - 2h

Notes
First imaging session with my new semipermanent observatory
NGC6888

NGC6888

NGC6888

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