Sh2-176

Sh2-176 is a faint planetary nebula in Cassiopeia. It has a surface brightness of 15.5 mag/arc-sec2 and a hydrogen-rich central star. It was discovered to be a planetary nebula by Sabbadin et al in 1977. It is approximately 490 light-years away with estimates for its age ranging from 24,000 to over 180,000 years old based on the computed kinematics (expansion rate and nebular diameter). Expanding at 19 km/sec, Sh2-176 has been estimated to span 3.1 to over 22.8 light-years across depending on the source. Its asymmetricity is believed to be the result of bow shocks involving the interstellar medium and the planetary nebula itself where, the brighter portion of the nebula represents the interaction of the nebula meeting up against the interstellar medium as it moves through space.  The central star associated with Sh2-176 is a blue subdwarf with a magnitude of 18.74.
TARGET
Nomenclature: Sh2-176
Right Ascension: 00:31:48.6
Declination:  +57:22:58.37
Size: 660 arc seconds
EQUIPMENT USED
Twin APM TMB LZOS 152 refractors
10Micron GM2000 HPS mount
Twin QSI6120 CCD cameras
Astrodon filters
IMAGE CAPTURE
Blue: 21x300"
Green: 21x300"
Red: 21x300"
Ha: 108x900" bin 1x1
Total Integration: 32 hours 15 minutes
Pixel scale: 0.530 arcsec/pixel
Field radius: 0.366 degrees
Capture dates: 4-9 August 2022
Capture location:  Fregenal de la Sierra, Spain
IMAGE PROCESSING:
CCDStack and Photoshop CS2
Ha image