When I first saw NGC 6826, I thought the "Blinking Planetary Nebula" moniker was related to it looking like an eye, but found it is named because it seems to appear visually using averted vision, and then disappear as one stares directly at it. In my capture I certainly see a staring and perhaps blinking eye shape, so I stand by my initial thought--though the
Hubble image looks much less like an eye.
NGC 6826 is between 2000 and 5000 light years away, so is something like 0.5 to 1.3 light-years in spread. It is estimated that the nebula contains about one-half the initial mass of the central star. Notable in the bright core region, visible in my image, are two bright patches on the right and left sides of the long axis of the nebula, which are known as Fast Low-Ionization Emission Regions, or FLIERS, that are moving outwards at supersonic speeds.
The core is very small, less than 30" in diameter, but exceptionally bright, while the faint outer shells are very dim--I was able to capture a little of those outer shells here in my image. Note the Hubble image doesn't show any of the fainter shells. My composite image is somewhat misleading, as the enormous difference in brightness required totally independent processing for the core and the outer shells. In the end I had three layers in Photoshop to combine, on top a layer with properly exposed stars, a middle layer with only the bright core but stars removed, to which I applied extensive Registax wavelets sharpening (only possible since the S/N on the core was incredibly good), and on the bottom a severely stretched image with the faint outer shells and again stars removed. I wanted more exposure time to really do those outer shells justice, but poor weather lately and the low altitude in the sky now, have forced me to complete this--for this year anyway.
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