This isolated nebula is located well above the galactic plane.
Avedisova concludes that it is ionised by the potential runaway O9.5 Iab supergiant
HD 165319, which may have been ejected from
NGC 6611, the central star cluster of M 16, the Eagle nebula, about 1.8 million years ago.
You can see a good image of this nebula in the
SuperCOSMOS data.
Polycyclic aromatic hydrocarbons (PAHs) have been detected in this HII region.[
1]
The O-star HD 165319 lies within or behind this nebula.[
2]
This star is given a B0 Ia class in a
1970 paper by Humphreys, but is, curiously, not included in her final catalog of OB stars and supergiants.
HD 165319 may have been ejected from NGC 6611 about 1.8 million years ago. [
3]
Notes
1. ^ Giard, M., Serra, G., Caux, E., et al. (1989). "The Galactic emission in
the 3.3-micron aromatic feature. I - Observations", Astronomy and
Astrophysics, Vol. 215, 92-100. [1989A&A...215...92G]
2. ^ de Wit, W. J., Testi, L., Palla, F., et al. (2004). "The origin of massive
O-type field stars. I. A search for clusters", Astronomy and Astrophysics,
Vol. 425, 937-948. [2004A&A...425..937D]
3. ^ Gvaramadze, V. V. & Bomans, D. J. (2008). "Search for OB stars running
away from young star clusters. I. NGC 6611", Astronomy and Astrophysics,
Vol. 490, 1071-1077. [2008A&A...490.1071G]