I was out of town two days. I get back to find the comet is leaving its outburst behind. Looking at the various posted images here you can see the nucleus getting steadily farther away from the bright outburst. Then both the inner and outer coma are getting much larger though the nucleus is fading. I'm reposting two images I've already posted and then one from tonight to show the changes.
First shot is at 1.003" per pixel and used 1/2" exposures as otherwise I was saturating the core. This was about 1 hour on Nov 25 UT. Then about 6 hours Nov. 25 I took the second shot. Its gone from a tiny core to a much larger core with an oddly elongated nucleus. This is reproduced at 0.500" per pixel using 2" exposures. This was done by changing from 2x2 binning to 1x1 binning. So I could expose longer but not saturate. The change in only 5 hours is amazing.
Then I had to leave town. I just got back and about fell off my chair when I took the third image. It was taken on Oct. 28 at 1 hour UT. It is again at 1.003" per pixel using 10" exposures. Compare it to the first one taken at the same scale 3 days earlier almost to the second. The nucleus has faded by a factor of 20 it appears as again I didn't saturate the core. But the big shock isn't that the coma shells have grown a lot. It's that the comet is leaving the outburst behind. The bright star isn't a star. It's the nucleus of the comet! Note how much larger it is than the field stars, even the two 11th magnitude stars also in the coma (ear the bottom). The coma is even larger than this shows. Bringing it out lowered overall contrast so I decided to go with this version. The color is changing as well.
Stay tuned for further developments.
Third image:
14" LX200R, L=10x10" RGB=5x10" all binned 2x2, STL-11000XM Paramount ME
Rick
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