| Planetary
Nebula
NGC 7293, PNG 036.1-57.1, PK 036-57.1, ARO 17 Visual Magnitude: 7.6 Magnitude of Central Star: 13.4 Apparent Diameter: 32.7' Distance: 530 ly Minimum requirements to view: binoculars or any telescope and very dark sky |
The Helix is at once easy and difficult to observe. By far the largest of the planetary nebulae in our sky, the low surface brightness of the Helix makes it difficult to spot unless you know what you are looking for. Any size scope can reveal it, and even binoculars will show it as a round, hazy, smudge of light.
The trick to successfully observing the Helix is to use a wide field of view. You will need relatively light-pollution-free skies and your lowest-power eyepiece. At least a 1/2o field of view is required to find this nebula. Something closer to 1o is optimum. This nebula extends some 13', making it over ten times as large as it's cousin, the famous Ring Nebula.
Look for a round spot in the sky that is slightly brighter than the background. Once found, use averted vision to see the large, slightly darker central region.
The view in a 6" telescope at 50x. North is down and East is right. An image of the nebula derived from the Digital Sky Survey has been overlaid to provide a realistic representation of what you may see in the eyepiece. You may need to adjust your monitor to see the nebula.
| Millennium
Star Atlas Vol III Chart 1355
Sky Atlas 2000 Chart 23 Uranometria 2000 Vol II Chart 347 |
