This 1.7 million year old nebula forms a ring around a central ionising star. A 2002 paper identifies the ionising star, which is visible in both hydrogen-alpha and infrared, as either a late O-class star or Wolf-Rayet star but does not cite a catalog identifier.
A magnificent infrared image of this nebula can be found here
and a different version (with more infrared frequencies visible) can be found on this Spitzer image
Another study that contains infrared images and concludes that the nebula is 1.7 million years old.[1
A detailed study of this HII region which determines the distance as 5300 +/- 400 pc and finds that this a ring around a central ionising O9.5V star.[2
1. ^ Zavagno, A., Deharveng, L., Comerón, F., et al. (2006). "Triggered
massive-star formation on the borders of Galactic H II regions. II.
Evidence for the collect and collapse process around RCW 79", Astronomy and
Astrophysics, Vol. 446, 171-184. [2006A&A...446..171Z]
2. ^ Cohen, Martin, Green, Anne J., Parker, Quentin A., et al. (2002).
"Mid-infrared, Hα and radio continuum images of an unusual HII region,
G308.70 + 0.60", Monthly Notices of the Royal Astronomical Society, Vol.
336, 736-746. [2002MNRAS.336..736C]