| Planetary
Nebula
aka PNG 204.1+04.7, PK 204+04.1, ARO 128 RA: 06h52m28.4s Dec: +09°58'17" (Monoceros) Integrated Visual Magnitude: 12.5 Angular Diameter: 6.9' Mean Surface Brightness: 25.3 Mag/arc-sec² Distance 1800 ly Minimum requirements to detect: 16-inch under dark skies with OIII |
Kohoutek
2-2 is a large, diffuse, ancient planetary nebula. Oddly, the appearance
of this nebula in the eyepiece is markedly different from that of the red-light
DSS image to the right. I have been unable to find a color image
of the planetary and it is in the southern unfinished zone of the online
second generation DSS where no blue image is available. I suspect
that the blue-light image would appear markedly different.
In my 18-inch f/4.5 at 94x this planetary was quite difficult, even with an OIII filter. With perseverance I was eventually able to detect an elongated, egg-shaped glow between two stars (as drawn in to the simulated eyepiece view below). This planetary is very obscure, so if you do detect it you can count yourself among a select group of people who have ever seen it.
The field in an 16-inch
f/5 at 90x. North is down and east is to the right.
| Millennium
Star Atlas Vol I Chart 202
Sky Atlas 2000 Chart 12 Uranometria 2000 Vol I Chart 183 Herald-Bobroff Astroatlas B-05 C-40 |
