The Ring Nebula is a planetary nebula about 2,000 light-years from Earth and measures roughly 1 light-year across. It is located in the constellation Lyra, and is a popular target for amateur astronomers.
But this new image, done as a collaboration between amateur astronomers Terry Hancock of Michigan and Fred Herrmann of Alabama, is amazing, with detail usually only seen from large ground-based observatories or space telescopes, particularly the detail of the gaseous outer shell of the nebula.
With over 25 hours of total exposure time, this is a remarkably deep exposure which explores the looping filaments of glowing gas. The collaborative effort combined data from two different telescopes, and both Hancock and Herrmann used Astro-Tech 12″ Ritchey-Chrétien astrographs.
Below is another view, a wide field version:
Hancock’s data is from 2012 and 2013 using a QHY9 monochrome CCD and Herrmann’s data is from an SBIG STT-8300 monochrome CCD. Data was collected over 14 nights and six one hour narrow-band hydrogen alpha exposures were taken in order to show the dimmer outer shell.
Hancock explained on G+ that the lighter hydrogen forms the outer reddish envelope while the heavier blue-green oxygen remains about the core. “The gases in the expanding shell are illuminated by the radiation of the central white dwarf, and the glow is still 200 times brighter than our Sun,” he said.
Also visible in the images is the barred spiral galaxy IC 1296.
Recent views from the Hubble Space Telescope of the Ring Nebula showed how the ‘ring’ is really more similar to a football-shaped jelly donut, and Hancock and Herrmann’s view shows that shape as well.