Another from the summer -- and the first processed in 2023 -- NGC 6820!

This is an emission nebula in the constellation Vulpecula, a small, faint constellation along the Milky Way. NGC 6820 isn't far from the more-popular Vulpecula nebula, the Dumbbell. The larger nebulous surrounding area is known as Sh2-86, and the star cluster associated with the nebula (NGC 6823) is about 6,000 lightyears away.

These emission nebulae are giant clouds of gas and dust; the young, energetic stars in the area blast out UV radiation that energizes the gases, causing them to glow. Hydrogen is the most dominant material, although this image consists of light from oxygen and sulfur as well, which both glow in the visible spectrum. The stellar winds of these stars are responsible for shaping the nebula. The dark balls of dust are Bok globules, which contain stars in the process of forming.

I don't see this nebula imaged as often, but it's not especially dim, for an astrophotographer with narrowband filters at least (one might even be able to make out that finger against the brighter background using a nebula filter under dark skies), and it's got a lot of cool detail like some other favorite emission nebulae.

The colors used here aren't the natural colors that the gases glow -- hydrogen and sulfur both glow deep red, while oxygen glows a blue-green. But in order to distinguish the different elements and the fine detail in this nebula better, I used the popular Hubble palette, where sulfur is assigned to red, hydrogen to green, and oxygen to blue. The green-colored hydrogen signal dominates the image, so it's common to reduce the green component to allow the others to shine through, as I have done here. Although I like to leave a little more green in the image -- some people kill it entirely, which I think makes for a less-attractive representation.

The 60s OIII frames are from a short period when I was having issues with guiding.