Planetary Nebula Gas Shell

So it begins...Looks like a hubble image it's so fuzzy, so I bumped up the sampling

So it begins...Looks like a hubble image it's so fuzzy, so I bumped up the sampling

Better, after increased sampling, and some work with the color ramp

Better, after increased sampling, and some work with the color ramp

Still improving.  More abuse of the color ramp

Still improving. More abuse of the color ramp

OK, good enough.  After more sampling and very fine adjustments to the color ramp

OK, good enough. After more sampling and very fine adjustments to the color ramp

I've been looking for a way to procedurally generate a believable gas shell around a white dwarf for a while now, and found it.
This all hinges off of a gradient texture, a noise texture, and a few color ramps.