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Comet 17P Holmes, October 26th, 2007

Original drawing made using lead pencil on white paper:

Same drawing reversed:

Comet 17P Holmes, October 26th, 2007, 3:25 - 3:50 UT. High clouds obscured the view from time to time and this combined with the light from the full Moon reduced transparency around 3.0, seeing 5 (fair).

TMB Optical 175mm f/8 refractor on its homemade Dobsonian-style mount. Magnification 47x-70x, field of view approximately 1.30 degrees. I estimated the comet to be around magnitude 2.5.

This is a remarkable comet. Through the telescope it reminds me of a large planetary nebula with a stellar pseudo-nucleus, inner coma or condensation and outer coma or bright envelope, all of which have a light yellow color to it. The stellar pseudo-nucleus has a fan shaped wedge of material coming off of it, and the outer coma has a gauze-like appearance to it. From time to time there appeared to be a fainter outer envelope outside of the outer coma but it is difficult to be certain with the clouds and moon light. Therefore I did not recorded it in the sketch.