SNR (SuperNova Remnant) G065.3+05.7 in HOO w RGB stars (Cygnus) - June 3,4,5,6,7,11,12,16,20,22 2023
TeleVue 127is - AIS6200MM
A-P 1 Mach2 AE, Baader 6.5nm NB & BB filters
4 Panel Mosaic
H,O: (167, 133 x 420s exposures, Bin 2x2, Gain 200)
R,G,B: (56, 51, 48 x 120s exposures, Bin 2x2, Gain 100)
Total Integration Time = 40.2 hours (excluding rejected frames)

Supernova remnants (SNRs) are the remains of a distant past supernova explosion that has long since dimmed. They are composed of both the material ejected from the exploding star in addition to swept up gases and dust in its radial path. Interestingly, all of the elements heavier than Iron (Fe) in the universe are believed to have been created by supernovae, and this image shows these (and other) elements being dispersed. Two colours are dominant in this image - red from the hydrogen present, and blue/green from excited oxygen ions that show where the material fronts are at much lower densities.
To me, this image of "SNR G065.3+05.7" begs for a comparison with its much younger sibling - "The Cygnus Loop" or aka "Eastern / Western Veils and Pickering's Triangle" - also in Cygnus. The Cygnus Loop is 7,500 years old while "G065.3 ..." is a much older 30,000 years. Both occuply about the same sky space, at roughly 4 degree, but "G065.3 ..." is both larger and farther away (2500 ly vs 1500 ly for Cygnus Loop) - which means it occupies over 6 times the volume. Cygnus loop is also brighter, making it more photogenic and also explains why "G065.3 ..." is stuck with a terrible name.
This image is a result of a four panel mosaic and shot at a sky resolution of 2.3"/pixel. This SNR is quite dim, requiring a lot of integration time and reasonably high camera gain. Furthermore, it is within a dense star field (in a 2-D sense only) and molecular cloud that also emits light and both serve to obscure the SNR. A lot of work was done to put normal coloured RGB stars in the image, but they had to be aggresively shrunk and dimmed to appreciate the SNR.
This image also contains a planetary nebula (PN), glowing hydrogen red near, but just above the "centre" of the image. For some reason, this tiny PN (PK064+05.1) also gets the prestigious name of "Campbell's Hydrogen Star" proving that the naming of astronomical objects is not based in meritocracy. That's OK though, the SNR gets all the silver and gold.
If you zoom in, you can see the star shining in true RGB colours. I have to point this out, because in hindsight - getting the RGB data seems like a waste of time.
The total integration time noted for this four panel mosaic, along with that for rejected frames, means that my refractor spent most of the clear nights in June on this single target.