This is the third part in my series on the Cep OB2 Association. The subject of this image, SH2-129, colloquially known as the Flying Bat Nebula, is an HII (ionized) region in the constellation Cepheus. This nebula, like the others in the larger Cepheus "Bubble", is the result of a blue hyper giant that is generating a powerful solar wind, blowing away the molecular cloud in which the star was initially born. The star in question, HD202214 (or HR8119), is of spectral type O9.5IV. It will survive only a short time, measured in a few millions of years, but will burn brightly, generating UV radiation and ultimately--in all probability--ending its life in a supernova.

This blue star, HD202214, found roughly in the middle of the image, is actually a double or multiple star. It is part of the Cepheus OB2 Stellar Association, a loose grouping of 50 O and B type stars. In the image you can see that there is very little red nebulosity (in this case ionized HII) near the star itself. The star's UV radiation and subsequent shockwave has burned it off and pushed the remainder outward. In those areas where you see concentrations of gas (as in the ridge lines near the bottom and to the left of the image), it is likely that there are protostars in hiding, much weaker entities resisting the stellar onslaught of HD202214.

Nearby to HD202214 is its life companion, the massive red giant variable, HD202380 (V419 Cep). Weighing in at 16.6 solar masses, this giant will also live a short life, likewise doomed to die in a supernova.

Quite oddly, many of the blue giants in the association have nearby red giant companions. In Part I of the series I showed you HD 206267, the blue giant system at the heart of the Elephant Trunk nebula. Its companion star is the famous Garnet Star, Mu-Cep. In Part II of the series, I introduced you to Lambda Cep, and its orange super giant companion, Zeta Cephei. As you look at other images, be on the lookout for these stellar pairings!

On the far left of the picture is a beautiful little reflection nebula caused by two notable Type B stars (among others), standing firm in the shockwave of HD202214. They are, on the left, LS III +59 6 (Type B1III) and on the right, HD 239626 (Type B0V) For me, the building nebulosity between these competing systems is a story in the making. What will happen? Which stars will survive? How will this cosmic slugging match end?

Finally, I should say something about "The Squid" (OU-4). At the center of Sh2-129 is the well-known Squid Nebula. It is a large O2 region and quite beautiful in its own right. It is, however, extremely difficult to photograph and while I was able to capture some of the O2 nebulosity using my OSC setup, I simply didn't put in the time nor do I have the processing skills to pull out that faint an image. Therefore, you will see no squid here! Hopefully you are not disappointed, but at least it won't be a distraction.

Honestly, and I hope you don't mind, but my interest at this time is actually with the HII regions of the larger Cep OB2 Association and their various histories and morphologies. Certainly, the extremely odd (unique and special) emissions from HD202214 that constitute "The Squid" are part of the story, but they merit their own effort and it will have to wait for another time. That said, if you'd like to teach me to pull out that lurking squid, please contact me!

As you no doubt know, nothing we image exists in isolation. Everything is interrelated and I find that the study of regions like this provides a fascinating context for our pictures, ultimately giving them meaning, history, and an impact beyond the images themselves. To that extent, each star matters, each cloud of HII, each patch of dust or dark matter, all of it! Thank you for reading my long description and I hope you enjoyed the journey and will take the time to make a comment. I will be shooting the end of the series when darkness returns to the realm. Stay-tuned!

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If you haven't already, please check out the other images in my Cep OB2 Series:

Part I: The Complexity of Phenomena. IC 1396 and the Power of Stars.

Part II: Lambda Cephei (λ Cephei), Sh2-134 and the Cep OB2 Association

Part IV: The Origins of Cep OB2, NGC7160, and Sh2-140