According to one source, this HII region, which is most likely ionised by a B2.5 V class star, lies at the edge of a 1000 solar mass molecular cloud in a similar direction to the Sh 2-192 to Sh 2-194 group of nebulae.
According to a 2007 paper by Russeil, Sh 2-196 may lie at the same distance as Sh 2-192 and Sh 2-193 (2400 +/- 320 parsecs), however she has identified a possible O9.5 class ionising star with a photometric distance of 5670 +/- 590 parsecs, suggesting that it may be much further away than the other nebulae.
Avedisova places Sh 2-196 in star formation region SFR 136.45+2.53
with 21 components, including the radio source KR 147B
, 4 masers and 9 infrared sources. Among the infrared sources are three distinct young stellar objects.
Russeil paper. [1
Most likely ionised by a B2.5 V class star.[2
Lies at the edge of a 1000 solar mass molecular cloud.[3
This HII region lies between W4 and W5.[4
1. ^ Russeil, D., Adami, C., & Georgelin, Y. M. (2007). "Revised distances of
Northern HII regions", Astronomy and Astrophysics, Vol. 470, 161-171.
2. ^ Hunter, Deidre A. & Massey, Philip (1990). "Small Galactic H II regions. I
- Spectral classifications of massive stars", The Astronomical Journal,
Vol. 99, 846-856. [1990AJ.....99..846H]
3. ^ Hunter, Deidre A., Thronson, Harley A., Jr., & Wilton, Charles (1990).
"Small Galactic H II regions. II - The molecular clouds and star
formation", The Astronomical Journal, Vol. 100, 1915-1926.
4. ^ Digel, Seth W., Lyder, David A., Philbrick, Amy J., et al. (1996). "A
Large-Scale CO Survey toward W3, W4, and W5", The Astrophysical Journal,
Vol. 458, 561. [1996ApJ...458..561D]