Sunday, November 25, 2007
Comet HolmesDuring the last few weeks I observed Comet Holmes on a few occasions, and I have seen it change gradually. The first time I got a chance to see Holmes was on October 30th. The core looked very bright and compact, surrounded by a more or less faint halo. There was a very sharp and distinct division between the border and halo. Right on the borderline between the halo and the core was a bright star visible. I observed Holmes with the 85mm Zeiss and a zoom-eyepiece at 60x. The field of view was a little more than 1 degree. The sketch below should give you an idea of the view. North is up and east is to the left.
Over the weeks I saw the halo growing in size. The core became less bright and the sharp boundary between core and halo started to vanish. Until now, the most beautiful sight of the comet was on the night of November the 17th. I observed the comet with the 12x60 Skymaster (Celestron) binocular mounted on the SkyWindow. The generous field of view of this binocular is 5.7 degrees. Comet Holmes had moved right up to the Alpha Persei Cluster and both the comet and the cluster were visible in the same field of view. The sketch below again should give you an idea. On this sketch North is to the left and and East is at the top (these strange directions are caused by viewing with the SkyWindow).
The halo looked very large and the core was still there, but it seemed more or less oval. As I mentioned earlier, the division between core and halo was not very distinct. In Alpha Persei I could detect three stars that showed some color. Alpha Persei was yellowish, and at two o’clock I detected a couple of contrasting stars. One seemed orange-red and the other seemed to be very light blue. The cluster and the comet formed a stunning pair, and I observed it for about an hour to an hour and a half. The sketch took me about 45 minutes.