Above: Latest attempt with the same data - April 2024.
SH2- 155 (Cave Nebula)
Sh2-155 (also designated Caldwell 9, Sharpless 155 or S155) is a diffuse nebula in the constellation Cepheus, within a larger nebula complex containing emission, reflection, and dark nebulosity. It is widely known as the Cave Nebula, though that name was applied earlier to Ced 201, a different nebula in Cepheus. Sh2-155 is an ionized H II region with ongoing star formation activity, at an estimated distance of 725 parsecs (2400 light-years) from Earth.
Sh2-155 was first noted as a galactic emission nebula in 1959 in the extended second edition of the Sharpless catalogue, being a part of the much larger Cep OB3 Association. Although Sh2-155 is relatively faint for amateur observation, some of its structure may be seen visually through a moderately sized telescope under dark skies.
Sh2-155 lies at the edge of the Cepheus B cloud (part of the Cepheus molecular cloud), and is ionized by young stars from the Cep OB3 association. It has been suggested that radiation from the hot O-type star HD 217086 is compressing the region, triggering the formation of a new generation of stars. A study of the region's young stellar objects by the Chandra X-ray Observatory and Spitzer Space Telescope shows a progression of stellar ages in front of the cloud, supporting the hypothesis of triggered star-formation.
Imaging telescopes or lenses: Takahashi FSQ130ED
Imaging cameras: FLI ML16200
Mounts: Takahashi EM 400 Temma 2M
Guiding telescopes or lenses: Takahashi FS60CB
Guiding cameras: QHY CCD QHY 5 II
Focal Extender / Reducer: None
Software: PHD 2, Pleiades Astrophoto PixInsight , Astro Pixel Processor (for stacking), Sequence Generator Pro SGP (for capture)
Filters: Astrodon Ha, L, R, G & B.
Accessories: Robofocus Focuser, ATIK EFW3
Original Resolution: 2700 x 1750
Dates: 12th Sept - 15th Sept '20
Frames:
Astrodon Ha 18 x 10'
Astrodon L 30 x 3'
Astrodon RGB 3 x 30 x 3'
Total Time: 9 Hours
Center (RA, Dec): (344.188, 62.408)
Center (RA, hms): 22h 56m 45.020s
Center (Dec, dms): +62° 24' 29.657"
Size: 85.7 x 55.5 arcmin
Radius: 0.851 deg
Pixel scale: 1.9 arcsec/pixel
Orientation: Up is 360 degrees E of N
Sh2-155 was first noted as a galactic emission nebula in 1959 in the extended second edition of the Sharpless catalogue, being a part of the much larger Cep OB3 Association. Although Sh2-155 is relatively faint for amateur observation, some of its structure may be seen visually through a moderately sized telescope under dark skies.
Sh2-155 lies at the edge of the Cepheus B cloud (part of the Cepheus molecular cloud), and is ionized by young stars from the Cep OB3 association. It has been suggested that radiation from the hot O-type star HD 217086 is compressing the region, triggering the formation of a new generation of stars. A study of the region's young stellar objects by the Chandra X-ray Observatory and Spitzer Space Telescope shows a progression of stellar ages in front of the cloud, supporting the hypothesis of triggered star-formation.
Imaging telescopes or lenses: Takahashi FSQ130ED
Imaging cameras: FLI ML16200
Mounts: Takahashi EM 400 Temma 2M
Guiding telescopes or lenses: Takahashi FS60CB
Guiding cameras: QHY CCD QHY 5 II
Focal Extender / Reducer: None
Software: PHD 2, Pleiades Astrophoto PixInsight , Astro Pixel Processor (for stacking), Sequence Generator Pro SGP (for capture)
Filters: Astrodon Ha, L, R, G & B.
Accessories: Robofocus Focuser, ATIK EFW3
Original Resolution: 2700 x 1750
Dates: 12th Sept - 15th Sept '20
Frames:
Astrodon Ha 18 x 10'
Astrodon L 30 x 3'
Astrodon RGB 3 x 30 x 3'
Total Time: 9 Hours
Center (RA, Dec): (344.188, 62.408)
Center (RA, hms): 22h 56m 45.020s
Center (Dec, dms): +62° 24' 29.657"
Size: 85.7 x 55.5 arcmin
Radius: 0.851 deg
Pixel scale: 1.9 arcsec/pixel
Orientation: Up is 360 degrees E of N
Sky Map
Annotated Image
