Comet Holmes: The Great Silver Celestial Jellyfish
Bob Townsend
This is a photograph of the Great Silver Celestial Jellyfish (aka comet Holmes) that I made on 8 December 2007. The image is twenty-one 60-second subs with my Takahashi E200 and Canon 350D DSLR combined in Images Plus. I did only 60-second exposures, so it wouldn't be necessary to use the tracking telescope. This was a totally unguided shot. The seeing was pretty poor that night as the jet stream was directly overhead. The field of view of this image is one by one and one half degrees, so you can see how big the comet is. For comparison, the diameter of the full moon is about one half of a degree.
Figure 1. The coma of Comet Holmes subtends a greater angle than that of the full moon. Photograph by Bob Townsend.
To see more of Bob Townsend's superb astrophotographs, enter his name in the search box at www.sas.org. Editor.
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