Sh2-129 Flying Bat Nebula & OU4 Squid Nebula

Pictures taken on Sunday 13th August 2017 from Brumano and from “Piani dell’Avaro”, Cusio (BG)

The Flying Bat nebula, Sh2-129, is a large emission nebula in the constellation Cepheus. With an apparent diameter of over 2 1/2 degrees in our sky, this faint Ha region is often overlooked due to the proximity of its much brighter celestial neighbour, IC 1396.

Above and to the right of Sh2-129 is the reflection nebula, vdB 140. While having no distinct features, the nebula is interesting because it appears to also be embedded within an HII region.

The “star” of this image is the enigmatic object, the Squid Nebula – OU4. Discovered by Nicolas Outters only a few years ago in June 2011, the Squid Nebula shines by the blue/green light of OIII – the forbidden line of doubly ionized Oxygen. Over a degree long, the object is extremely faint and even more mysterious in its origin.

Originally believed to be a planetary nebula, astronomers have since concluded that it is not such an object. A recent investigation suggests Ou4 really does lie within Sh2-129 some 2,300 light-years away. Consistent with that scenario, Ou4 would represent a spectacular outflow driven by HR8119, a triplesystem of hot, massive stars seen near the center of the nebula. The truly giant Squid Nebula would physically be nearly 50 light-years across.

 

Equipment:
Takahashi FSQ 106 EDXIII F/5
CCD Moravian G2 8300 and CCD Sbig 8300
Guide scope TecnoSky 60/228mm
Guide camera Starlight Xpress Lodestar X2
Mount Sky-Watcher AZ-EQ6 and Astro-Physics 1100 GTO

Shots:
RGB 6 x 600s  (thanks to Efrem Frigeni)
OIII 20h (Massimiliano Zulian & Efrem Frigeni)
H-Alpha 16 x 1200s (Massimiliano Zulian & Efrem Frigeni)

Processing:
Pixinsight 1.8, Photoshop CC (2015)