Hemisphere:  Northern  ·  Constellation: Cepheus (Cep)  ·  Contains:  NGC 7822
Sharpless 171, 


            John Renaud
Sharpless 171
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Sharpless 171

Sharpless 171, 


            John Renaud
Sharpless 171
Powered byPixInsight

Sharpless 171

Technical card

Imaging telescopes or lenses: Sky-Watcher Esprit 150ED

Imaging cameras: FLI ML16200

Mounts: Astro-Physics 1100GTO

Guiding cameras: SX Ultrastar

Software: PixInsight  ·  Sequence Generator Pro  ·  Photoshop  ·  PHD2  ·  StarNet++

Filters: Chroma OIII 3nm  ·  Chroma SII 3nm  ·  Chroma Ha 3nm

Accessory: SX Maxi Filter Wheel

Dates:June 28, 2019July 5, 2019July 9, 2019July 18, 2019Sept. 7, 2019Sept. 8, 2019Sept. 9, 2019Sept. 23, 2019Sept. 24, 2019Sept. 25, 2019Sept. 26, 2019Sept. 29, 2019Sept. 30, 2019Oct. 1, 2019Oct. 2, 2019Oct. 21, 2019Oct. 22, 2019Oct. 23, 2019

Chroma Ha 3nm: 78x900" (19h 30') -25C bin 1x1
Chroma OIII 3nm: 79x900" (19h 45') -25C bin 1x1
Chroma SII 3nm: 80x900" (20h) -25C bin 1x1

Integration: 59h 15'

Darks: 20

Flats: 50

Bias: 200

Avg. Moon age: 14.51 days

Avg. Moon phase: 35.12%

Basic astrometry details

Astrometry.net job: 3280440

RA center: 0h 4' 1"

DEC center: +67° 9' 3"

Pixel scale: 1.148 arcsec/pixel

Orientation: 91.243 degrees

Field radius: 0.898 degrees

Resolution: 4402x3517

Locations: Backyard, Magnolia, TX, United States

Data source: Backyard


Sharpless 171 is a large emission nebula located approximately 3,200 light-years away in Cepheus, within the larger star forming complex NGC 7822. Near the top left of the structure is a young cluster of stars named Berkeley 59, which is largely responsible for ionizing and illuminating the nebula. This cluster contains many stellar "baby stars" that are no more than a few million years old. Interestingly, the bright central star pointed to by the pillar isn't associated with SH2-171 - it's actually a foreground star, at about 300 light-years away.

This was acquired mostly last Fall and I finally just recently found the right combination of both time and motivation to finish processing it. Even at 60 hours of data, it was a challenge to bring out contrast while retaining some of the "murky" feel of this region and not over smoothing it... I think I got there... after about 8 restarts! :-P


Sky plot

Sky plot


Sharpless 171, 


            John Renaud