Sharpless 129 (Sh2-129) & Ou4
Flying Bat & Squid Nebula. Emission & Planetary Nebulae, Cepheus
Sharpless 2-129 (Sh2-129) is a Ha emission region in the constellation of Cepheus, Sh2-129 is also known as the Flying Bat Nebula, and it also contains the Squid Nebula, designated Ou4, a mysterious, squid-like apparition. This nebula is very faint OIII emission, but also very large & spans about one degree in length.
American astronomer Stewart Sharpless discovered the large nebula Sh2-129 on the 48 inch Schmidt telescope photo plates of the Palomar Observatory Sky Survey. In 1959 he published his discovery together with 313 H-II regions in a catalogue. He classified it as of irregular shape with 140 arc minutes diameter some amorphous to filamentary structure with intermediate brightness, the nebula later became known as Flying Bat Nebula.
In May 2011 the French amateur astro-photographer Nicolas Outters imaged Sh2-129. He took several 30 minutes exposures with a Takahashi FSQ-106 refractor and SBIG 6303e CCD camera using narrowband filters, totaling 12.5 hours. After combining the images taken through the O-III filter he discovered a large structure that seemed to have no correlation with the nebula of Sh2-129. He called it “Le Calamar”. Having been unable to find any images of Sh2-129 which showed such a structure, he contacted the French astrophysicist Agnès Acker who did precise studies of this strange object and confirmed an important presence of Oxygen III. The nebula was given the designation Ou4, for the fourth nebula discovered by Outters.
Ou4’s bipolar shape and emission are consistent with it being a planetary nebula, the gaseous shroud of a dying sun-like star, but its actual distance and origin are unknown. A new investigation suggests Ou4 really lies within the Ha emission region SH2-129 some 2,300 light-years away. Consistent with that scenario, the cosmic squid would represent a spectacular outflow of material driven by a triple system of hot, massive stars, cataloged as HR8119, seen near the center of the nebula. If so, this truly giant Squid Nebula would physically be nearly 50 light-years across.
American astronomer Stewart Sharpless discovered the large nebula Sh2-129 on the 48 inch Schmidt telescope photo plates of the Palomar Observatory Sky Survey. In 1959 he published his discovery together with 313 H-II regions in a catalogue. He classified it as of irregular shape with 140 arc minutes diameter some amorphous to filamentary structure with intermediate brightness, the nebula later became known as Flying Bat Nebula.
In May 2011 the French amateur astro-photographer Nicolas Outters imaged Sh2-129. He took several 30 minutes exposures with a Takahashi FSQ-106 refractor and SBIG 6303e CCD camera using narrowband filters, totaling 12.5 hours. After combining the images taken through the O-III filter he discovered a large structure that seemed to have no correlation with the nebula of Sh2-129. He called it “Le Calamar”. Having been unable to find any images of Sh2-129 which showed such a structure, he contacted the French astrophysicist Agnès Acker who did precise studies of this strange object and confirmed an important presence of Oxygen III. The nebula was given the designation Ou4, for the fourth nebula discovered by Outters.
Ou4’s bipolar shape and emission are consistent with it being a planetary nebula, the gaseous shroud of a dying sun-like star, but its actual distance and origin are unknown. A new investigation suggests Ou4 really lies within the Ha emission region SH2-129 some 2,300 light-years away. Consistent with that scenario, the cosmic squid would represent a spectacular outflow of material driven by a triple system of hot, massive stars, cataloged as HR8119, seen near the center of the nebula. If so, this truly giant Squid Nebula would physically be nearly 50 light-years across.
Telescope: Planewave Delta Rho 350 f3.0
Mount: Astro Physics 3600GTO “El Capitan”
Camera: ZWO ASI461MM pro / EFW-7
Guider: ZWO OAG-L-68 / ZWO ASI174mm Mini
Filters: Astrodon II 50mm Sq LRGB
L: 28×5 mins = 140 mins, R: 24×5 mins = 120 mins, G: 24×5 mins = 120 mins, B: 24×5 mins = 120 mins
OIII: 89x5m = 445 mins
Total Imaging Time: 15h 45m
Data Imaged remotely on 8 nights during September 2024.
Data acquisition & Processing by David Churchill.
None
