I declined to label this image as the Running Chicken Nebula, because I don’t think it looks remotely like a chicken, running or at rest, from any orientation. I prefer the designation ‘λ Centauri nebula’, which name it acquires because it is in the same line of sight of the star λ Centauri, the brightest and most prominent star in the image.
IC 2944 is an open cluster of newborn stars whose ferocious radiation is ionizing and lighting up the surrounding HII gas (IC 2948 in the overlay). The nebula and cluster are about 6500 light-years away, and (depending on how you measure it) the nebula has a diameter of about 142 light years. Note that the λ Centauri star is itself not part of the nebula; it is much closer to us, about 420 light years away.
If you zoom in you can see black flecks in the central part of the nebula. These type of flecks are called Bok Globules (after Bart Bok ,
who noted them in a publication in 1947 along with Edith Reilly), and these specific ones are known as Thackeray’s Globules, after A. David Thackeray, who discovered them in 1950. Bok Globules are cold, dense clouds of gas; they are probably fragments of a larger clouds that were annihilated by the intense radiation from the nearby cluster of young hot stars. Most Bok Globules, which on average contain about 10 solar masses and are a light year across, collapse to form double- or triple-star systems; however, the Thackeray Globules will probably not make it that far. Their “sharp” edges are a sign that they are being scoured away by ferocious interstellar winds from the new, hot stars in the cluster.
IC 2872, the bright nebular region at left center, has an interesting “lobe” structure – ionized gas demarcated by lanes of cooler dust – similar to the Trifid nebula.
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