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Comet Pojmanski (C/2006 A1), March 5th, 2006

Original drawing made using white pencil on black paper:
Same drawing on a white background:

Comet Pojmanski (C/2006 A1), March 5th, 2006, 9:15 - 10:10 UT, seeing 5, transparency 5.3.

TMB Optical 130mm f/9.25 refractor on Super Polaris mount. Magnification 60x, field of view approximately 1.3 degrees. West is at the top of this sketch, east to the bottom, north to the left and south to the right.

The comet had a relatively bright pseudo-nucleus and coma and appeared light blue in color. The coma had a delicate gossamer or wispy glow to it like a nebula, reminding me in some ways of fine tissue paper.

The tail was faint and it took time to see and record the detail. It became somewhat easier as the comet climbed from 10 degrees in elevation at the beginning of the observing session to 20 degrees at the end. I tried several techniques to help see the detail better, including gently tapping the tube assembly, and moving the telescope back and forth. This helped to bring out additional detail because the eye is better able to pick up faint low-contrast detail when it is moving.

Another technique I used was to place the comet outside of the field of view and let it drift back into view. This helped me to detect a change in sky background and see and record the tail. This technique was used by the 19th century Harvard astronomer George Phillips Bond to help detect faint detail in deep-sky objects and comets.

From these techniques, as well as using averted vision, I was able to see the both the gas and dust tail. The gas tail, except for a brighter portion that extended off towards the 11:00 o'clock position, extended almost straight back from the coma towards the west or top of the field of view and appeared striated. A feathery dust tail was visible on the south or right hand side of the coma.