I captured some images of K4-55 in July 2020 and determined I needed a lot more images as this interesting nebula's outer spiral structure is quite faint. The entire nebula is only around 16th magnitude (visual). It wasn't in a good spot in the sky again until July came around in 2021. This time I had a duoband Ha/OIII filter so I captured a 32 images with it and blended the resulting duoband stack with the UHC stack of 9 images from 2020 to get a pretty decent result. I combined this data with IRCut image data from 2020 and 2021 to provide truer color stars.

The bright inner core is about 30 arc seconds across while the outer faint nebula is 92 by 51 arc seconds in size. The outer arms give the impression of a red spiral galaxy or maybe even a black hole with an accretion disk! The black hole nebula might be a catchy name. A paper from 1996 on this unusual object interprets it as a bipolar planetary nebula viewed nearly pole on. They suggest the spiral pattern is due to rotation during several episodes of mass ejection. (I am guessing some sort of stellar or substellar companion slowly orbiting the progenitor star might help produce this structure?)

Paper abstract can be found here:
https://ui.adsabs.harvard.edu/abs/1996ApJ...456..651G/abstract

The lack of an obvious central star means no Gaia parallax data is available to give a good distance estimate. Based on the size and assuming 1 to 2 light years in diameter would put it somewhere between 1500 and 3000 light years away.

It appears that this entire field has some tenuous Ha clouds scattered about, which just barely showed up in the duoband data. I did not attempt to bring these out and instead allowed them to drop into the sky background. The star magnitudes in both the UCAC4 and APASS databases seem not to provide reliable B-V color indexes for color balance so I had to do some guessing based on color temperature of some of the field stars that was available within Gaia mission data in order to color balance the star image.