Rarely if ever imaged on it's own, this diffuse nebula SH2-22 is located in Sagittarius, close by it's famous neighbour - M8.
This is a ring nebula surrounding the O8 III giant 63 Ophiuchi (HD 162978), which lies at the edge of the Sgr OB1 association in the Sagittarius arm.
Reminiscent of butterfly wings, the nebula is rich in Ha and less so in S2.
The bright central star is 63 Ophiuchi.
I attempted gathering O3 data but nothing showed up after an hour, so I have created a bicolour image - Ha>Blue & S2>red with added LUM & RGB stars in the mix.
Wikipedia mentions the following... 63 Ophiuchi is an O-type giant star in the constellation Sagittarius. In 1983, astronomers from the Sternberg Astronomical Institute in Moscow, Russia identified a faint, shell-shaped nebula surrounding the star that was being excited by the star's energy. Named Sharpless 22, this ring-shaped nebula has a double-shell structure with an inner envelope spanning 45–50′ (9–18 pc), surrounded by a diffuse envelope some 65–80′ (14–29 pc) across. At an estimated mass loss rate of (6–8) × 10−6 M☉/yr, it would take the star about (1–5) × 105 years to produce such a nebula from the outflow of its stellar wind.
Taken from my Bortle 6-7 light polluted backyard in Melbourne.
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