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]

Data source Davide Coverta

Optic RC8 f/6
Camera QSI 683 WS
Filters Astrodon Ha L, R, G, B
Mount NEQ6 with EQASCOM
OAG with Lodestar
Frame center
RA 20:12:16 DEC 38:18:54 J2000
30th July 2018
Astrobioparco di Felizzano, AL, Italy
Exposures Ha - 22x1200s @-15C bin 1x1
L 22x900s bin 1x1
R 6x600s bin 2x2
G 6x600s bin 2x2
B 6x600s bin 2x2

Integration time - 15h50m





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