(via APOD: 2012 October 4 - NGC 7293: The Helix Nebula)
Reaching back a week or so here, but this eyeball-like version of NGC 7293, the Helix Nebula, seems good for anytime in October, no?
Look out toward Aquarius with a decent telescope and you can see the death-throes of a Sun-like star. These planetary nebula (a remnant name, leftover from when astronomers didn’t know what these blob-ish things in the sky were, just too fuzzy to be a point-source like a star, they have nothing to do with planets) are the results of the various stages of fusion starting and stopping inside a star, throwing off layers of gas as the star expands and contracts.
This particular image is impressive for the amount of exposure time that went into it, a total of 58 hours, carefully collecting narrow-band data (just light-collecting would be broadband, this is limited to particular wavelengths of light) for hydrogen-alpha (red) and oxygen (blue-green). Though the nebula seems simpler in quick views:

The true geometry is complex, as gasses expelled at different times begin to collide.
NGC 7293: The Helix Nebula
Image Credit & Copyright: Martin Pugh
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