Sharpless 2-115 is an emission nebula just North and West of Deneb, in the constellation Cygnus. It displays a chaotic morphology of gas emissions and dark nebulae. In the relatively high-resolution image presented here, pillars and Bok globules can be readily identified. Adjacent to Sh2-115 is a round structure originally cataloged as a planetary nebula. Sh2-116 was included in the assigned the catalog number Abell 71 in 1966 and hypothesized to be a planetary nebula by Perek and Kohoutec in 1967 (Perek, L. & Kohoutek, L. 1967, Catalogue of Galactic Planetary
Nebulae) . A morphological study by Pismis, Hasse, and Quintero in 1991 (
https://iopscience.iop.org/article/10.1086/132891) reclassified Abell 71/Sh2-116 as an HII region. One of the pieces of evidence cited in the 1991 study is the lack of OIII signal in Sh2-116. With modern cameras, the image presented here as well as many other amateur images demonstrate significant presence of OIII signal in Sh2-116. Perhaps the conclusions of Pismis et al should be re-evaluated in light of higher quality available data.
Data for this image was collected during Summer 2023. Out of the 55 hours of collected data, close to 42 hours of data were used to generate this image. Data was pre-processed in Pixinsight, color mapping was performed in Photoshop according to modified SHO palette, and final image processing was completed in Pixinsight. RGB stars were used in place of narrowband stars.
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