Comet SWAN Appears to be Dimming

I got my first good look at the comet SWAN in a few days today and it was far from impressive. Matters were not helped by the fact that a 60-70% full moon was high in the sky but seeing was perfect so I was still expecting a good show. SWAN has moved quite a distance away from M13 at this stage so comparisons are getting harder but the comet is definitely dimmer than it was on October 27th. Then the comet was significantly brighter than M13 (mag 5.9) whereas today SWAN appeared to be somewhat dimmer than the cluster. To try get a more accurate estimate of the magnitude I jotted down the star field and then looked for a star that was about the same brightness as the comet when de-focused to the same size as the comet. There were two bright (in binoculars) stars near the comet, SAO 85028 (mag 6.3) and SAO 85001 (mag 5.6). The comet was definitely dimmer than SAO 85001 and looked to be very very similar in brightness to SAO 85028. This leads me to estimate the magnitude at between 6.0 and 6.5 with 6.3 being my best estimate.

[tags]SWAN, Comet, Astronomy[/tags]