Sh2-188 is one of the dimmer objects that I imaged during our recent trip to the dark skies at Dell City, Texas.  

Sh2-188, also called the Dolphin Nebula or Shrimp Nebula, is a planetary nebula – the gases expelled from a star before it becomes a white dwarf, lit up by that star.  It’s located in the Milky Way, approximately 2770 light years away, and it’s approximately 8.2 light-years across, giving it an apparent size of 10 arcminutes.  It’s estimated to be 22,500 years old.  

The nebula’s bow shape (as opposed to a circular shape) is theorized to be due to its relatively high velocity interaction with the interstellar medium.

The objects in our galaxy never cease to amaze me!

Camera geek info:

• Canon EOS 60D in manual mode, 3 minute exposure, ISO 2000
• Intervalometer
• Williams Optics Zenith Star 73 III APO telescope
• Williams Optics Flat 73A
• iOptron CEM40
• Dell City, Texas Bortle 2-3 dark skies

Frames:

• October 9, 2023 
  • Run 1
    • 59 3 minute lights 
    • 30 0.01 second flats
    • 30 0.01 second flat darks
  • Run 2
    • 76 3 minute lights 
    • 30 1/400 second flats
    • 30 1/400 second flat darks
  • 17 3 minute darks

Processing geek info:

• PixInsight
• BlurXterminator
• NoiseXterminator
• StarXTerminator
• Generalized Hyperbolic Stretch