Planetary Nebula NGC 2022
NGC 2022 was discovered on 28th December 1785 by Wilhelm Herschel with his 18.7 inch reflecting telescope and cataloged as IV 34. He wrote about it: «Considerably bright, small, nearly round, like a star with large diameter, with 240x like an ill defined planetary nebula.» 
NGC 2022 is a young planetary nebula with two visible shells. According to the Vorontsov-Velyaminov classification, it is described as a regular disk with a ring structure (IV, II).
Sabbadin et al. (Astron. Astrophys., 136, 193, 1984) have derived the following model for NGC 2022: The main part of the nebula is an oblate spheroid with moderate eccentricity. The axis ratio of length to width is 1.2. The whole complex is surrounded by a fainter, nearly spherical region that is expanding less rapidly than the central region. Assuming a distance of 2100 pc for the planetary nebula, this results in a diameter of 0.65 light years.
|Designations||PN G196.6-10.9: NGC 2022, PK 196-10.1, ARO 61, VV 23, VV' 34|
|Right Ascension (J2000.0)||05h 42m 06s|
|Declination (J2000.0)||+09° 05' 18"|
|Radial Velocity||+14.0 km/s ± 2.0 km/s|
|Expansion Velocity||26. km/s (O-III)|
|C-Star Designations||AG82 49, HD 37882, PLX 1306|
|C-Star Magnitude||15.89 mag (B filter)|
The planetary nebula NGC 2022 lies in the constellation of Orion between Betelgeuse (α Orionis) and Meisse (λ Orionis). (one third of the way from λ Orionis to Betelgeuse, just under 2 degrees). Surrounding mag 3.4 Meissa are numerous stars arranged in a conspicuous pattern that appears to the unaided eye like a loose, open star cluster. From there you come across the small nebula after almost 2 degrees or about a third of the distance between Meissa and Betelgeuse. The best observation time is October to February.
200 mm aperture: The PN appears as an almost circular object. At 80 km/h Mistral neither the ring nor the central star could be seen. The very small extent of NGC 2022 requires high magnifications and therefore reasonably good seeing.
250 mm aperture: Although only just visible at 50x, at high magnification the nebula reveals a ring-shaped disk about 25 arc seconds in diameter which appears completely black on the inside.
300 mm aperture: Here the nebula already looks less even. A slight elongation is visible at position angle 15 degrees, the extent of the structure is 25" x 20". There are bright points at the two outer ends of the ring, with the southern one appearing more conspicuous. At 450x magnification, the nebula is clearly ring-shaped but still lacks a central star.