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Comet Machholz (C/2004 Q2), January 2nd, 2005

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

Comet Machholz (C/2004 Q2), January 2nd, 2005, 1:40 - 3:00 UT, seeing 5, transparency 5.3.

TMB Optical 175mm f/8 refractor on alt-az mount. Magnification 70x - 100x, field of view approximately 1.1 degrees. North is at the top in this sketch, west is to the left.

The comet had a relatively bright outer coma and smaller inner coma. The pseudo-nucleus appeared stellar. The outer coma, inner coma and pseudo-nucleus appeared light green in color.

Three tails appeared to emanate from the outer coma of the comet. The first was the ionized gas tail, which extended towards the northeast. It appeared multithreaded and was the longest of the three tails. It was also the faintest of the three tails, so took some time to determine its length and shape. I have found in the past that sometimes while intently studying a faint astronomical object the eye can become fatigued over time, which makes it harder to see the faint detail. One technique I have found useful to help see this detail is to sit back in my observing chair, close my eyes and take several long deep breaths, in through the nose and out through the mouth. This has the added advantage of supplying the brain with more oxygen. Using this technique I found it easier to see the fine detail in the tails.

The second was the dust tail, which extended towards the southwest and them curved towards the southeast. Near the head of the comet this tail had a very pronounced feathered appearance to it, as if there were fine streams or strands of material coming off of the comet. Further back in the tail these streams or strands became less noticeable as they seemed to merge. The dust tail was the brightest of the three tails.

The third tail extended towards the east. It was the shortest of the three tails.