| Planetary
Nebula
aka PNG 326.7+42.2, PK 326+42.1, Abell 37 Integrated Visual Magnitude: 14.9 Apparent Diameter: 42" Magnitude of Central Star: 17.7 Mean Surface Brightness: 22.8 mag/arc-sec2 Minimum requirements to view: 6-inch scope under dark skies with OIII or UHC filter |
IC 972 is a nearly the lone bastion in Virgo for lovers of planetary nebulae. There are only three other planetaries in this constellation, where galaxies rule, and only one other (the Bat Symbol) is generally visible in amateur instruments.
This one is smaller than the planetaries most people observe, so be sure to use enough magnification (at least 175x). It is visible at low powers (100x), but not obvious. Some people report seeing a blue-green color.
In my 18-inch f/4.5 IC 972 appears as a faint, round smudge at 97x. It's not obvious, but once found I could hold it visible without averted vision. It appeared to possibly be brighter on the south end, but I wasn't certain. The OIII filter increased the contrast. At 260x a faint central star could be made out embedded in the nebula. I also saw hints of some sort of structure. The nebula didn't didn't jump right out at me like many smaller planetaries do, apparently because of its relatively low surface brightness.
The field in an 8-inch f/8 at 75x. North is down and east is to the right.
| Millennium
Star Atlas Vol II Chart 840
Sky Atlas 2000 Chart 14 Uranometria 2000 Vol II Chart 331 |
