This is an apparently large and distant HII region that is obscured by foreground dust. It consists of 44 thousand solar masses of ionised gas and is at least 3.9 million years old. The stars ionising the gas are unknown and are probably obscured by the foreground dust.
Avedisova locates Sh 2-183 in star formation region SFR 123.20+2.83
, with 16 components, including a water maser and 8 infrared sources. One of these infrared sources is the young stellar object IRAS 00468+6527
This object shows an extended irregular structure at radio frequencies as this 2.7 GHz image
taken with the Effelsberg 100m radio telescope reveals.
I've used IPHAS
hydrogen-alpha data to create a black and white image of this highly obscured nebula here
Sh 2-183 is visible as a diffuse nebula bordered by more compact emission sources in this IRAS infrared image
If this object is really located at 7000 parsecs, then the size in the radio image suggests that it may be one of the largest star formation regions in the outer galaxy. Note, however, that streaming motions in the Perseus arm can result in exaggerated distance estimates if velocity data is used alone to determine an object's distance (and the current distance estimate is, indeed, based on gas velocity).
This is a large HII region that is mostly obscured by foreground dust. It consists of 44 thousand solar masses of ionised gas and is at least 3.9 million years old. The star or stars ionising the gas is unknown and is probably obscured by the foreground dust. [1
1. ^ Landecker, T. L., Anderson, M. D., Routledge, D., et al. (1992).
"Sharpless 183 - an H II region in the Perseus arm", Astronomy and
Astrophysics, Vol. 258, 495-506. [1992A&A...258..495L]