Thursday, October 25, 2007


After the comet cleared the tree branches, at 10:50 p.m., I took a good look.

It is somewhat brighter, and a bit bigger. I don't think it has increased a lot in size, but some. With a 7mm Nagler in the 10" f/5.7 CPT, I was running 207X and the overall comet took about a quarter of the field of view. That would put it at 6 arcminutes. I also looked with a 12 Nagler giving 120X.

The brighter portion of the comet is still around 2 arcminutes. The nucleus is a bright golden yellow stellar point, offset slightly SSW. A bright yellow/cream colored fan of ejecta extends SSW from the nucleus. At times I felt the southern edge of the fan would show some movement, as if a pinpoint of brightening was occurring - extending into the edge of the fan, and perhaps feeding the fan itself.

Around the nucleus and ejecta fan was a bright circular glow, more pronounced on the fan side. Outside that was a darkened ring, which on the fan side was mostly interrupted. This darkened ring was enclosed by a bright soft outer ring, and that defined the end of the "bright" portion of the comet. If not for the fan and bright inner glow, the bright outer ring would have made the view as annular, maybe it could still be called that though. The darker part inside the bright outer ring appeared to be gray tinged with red to me.

Beginning at the outside edge of the bright outer ring, a very dim glow extended away from the comet. It appeared to extend an additional 2 arcminutes around the bright "outer" ring. The dim glow was easier to view at 120X than at 207X.

I hope this comet is still putting on a show in a few more days. It would be great to see it under dark skies.

More tomorrow... this is a really unusual comet!

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