Our 7th deep sky target, imaged from the remote observatory in Portugal by the AstroDarkTeam  composed of Pascal Gouraud and Stéphane Rolland.
We have been installed 18 month ago and already more than 550 hours of imaging!
Thanks again to the French Astro ARO team for the efficient and effective management of this superb site that hosts us.

We propose this time the Crescent Nebula (on the left) and the Soap Bubble Nebula (on the right),these two beauties of the sky evolve within an ample clouds of gas and dust drift through rich star fields along the plane of our Milky Way Galaxy toward the Cygnus constellation.

Discovered by William Herschel in 1792, the Crescent Nebula NGC 6888 is an emission nebula of magnitude 7.4, 5,000 light-years from us, it is located in the constellation Cygnus on the Deneb-Albireo line. Spanning 25 light-years, it is seen from Earth at an angle of 17 minutes of arc, roughly corresponding to a half-full moon.This envelope of matter is produced by a star of a very particular type, a "Wolf-Rayet star". Wolf-Rayet (WR) type stars are hot stars, probably originating from stars of spectral type O and B ( i.e. the hottest and most massive stars in existence) which have just left the main sequence and are therefore approaching the last stages of their life. The researchers estimate that WR-136 should explode as a supernova in the "near" future (on the scale of the Universe), within 100,000 to 1 million years.The Crescent, visible in the photograph presented here, therefore materializes the zone of influence of the stellar wind of the central star WR-136, whose surface temperature is extremely high and estimated at 70,000K. This star generates fast stellar winds which ionize the bubble of matter ejected by this star 400,000 years ago. This nebula is of considerable size since it extends over 25 light years in length! By way of comparison, the heliosphere of the Sun, i.e. the zone of influence of its solar winds, does not exceed 12 light-hours.

To its right we can see the graceful soap bubble nebula generated by the same phenomenon but smaller in size and almost spherical in shape. This  soap bubble nebula, or PN G75.5+1.7, is a planetary nebula. It was discovered by amateur astronomer Dave Jurasevich using an Astro-Physics 160mm refractor telescope with which he photographed the nebula on June 19, 2007 and July 6. 2008. The nebula was later independently noted and reported to the International Astronomical Union by Keith B. Quattrocchi and Mel Helm who imaged PN G75.5+1.7 on July 17, 2008. The nebula is 260″ in angular diameter with a central star of magnitude 19.45.

Technical Details :
239 images for a total of 30 h have been integrated between the September 22th 2022 and the November 05th 2022. To build this HOO image, we used 9.5 h for HA, 12.75 h for OIII, 2.75 h for R, 2 h for G, 2.75 h for B from a TOA telescope 130mm in diameter, 1000mm focal length, Moonlite Nightcrawler 35 focuser/rotator,
ASI2600MM monochrome camera cooled to -10 degrees, ZWO filter wheel with 36mm Chroma SHO 3nm and LRGB filters.
Autoguiding optical splitter ZWO with Camera ASI290MM, EQ8-R Mount Software MaxPilote, The Sky X Pro, Focus Max V3.
PixInsight processing.