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Reports from Geisei Observatory <November 19, 2007>

A photograph of Comet Holmes by Geisei's 60cm reflector

    Comet Holmes has undergone drastic changes in appearance and color. I took photographs using the 60cm f/3.5 reflector on the morning of November 19. The comet fills the photographic frame, which is more than 30' wide. A partially opaque, extremely beautiful blue coma envelopes a white central condensation. A slightly blurred nucleus and faint background stars are clearly seen through the coma. The tail remains short. It is exciting to see how the comet's brightness, appearance, and color are going to change. "Comet Holmes, are you a ninja in space?"

The following is the observation at Geisei:
Nov. 19.68UT total magnitude 3.3 coma 33' tail 5' 7x50B

    With the naked eye the comet at first looked far fainter compared with a nearby 2nd magnitude star. But with better dark adaptation the faint coma becomes more easily visible and the comet's overall brightness increases. This is what is called the total magnitude of the comet. At a darker observing site the total magnitude tends to be estimated brighter than from an urban site.

5-minute exposure from 23:35, November 17,. 2007
60cm f/3.5 reflector, ISO 400 film

Copyright (C) 2007 Tsutomu Seki.