Canon 350D Hap Griffin Baader Mod
9x600sec at iso 1600
30 Darks/Flats/Bias
APM/TMB 130/780 with APM field flattener
Baader 7nm H alpha filter

A full frame image for scale with other images - to show how large this "largest of the planetary nebulae" really is.

The Helix nebula (NGC 7293) in Hydrogen Alpha light taken the same night as the previous M16 (bad seeing, thin clouds, and bloated moon). I had planned on many hours of integration time, but the clouds got too bad around 1 am, so I had to be content with 90 minutes.

The Helix Nebula is one of the closest of all planetary nebulae: Lying at a distance of perhaps 450 light years and spanning 2.5 light years. The Helix Nebula is an example of a planetary nebula, a nebula created at the end of the life of a Sun-like star. The outer gasses of the star expelled into space appear from our vantage point as if we are looking down a helix. The remnant central stellar core, destined to become a white dwarf star, glows in light so energetic it causes the previously expelled gas to fluoresce.

September 18, 2008