December 30, 2004

C/2004 Q2 (Machholz) - Dec. 30, 2004

The above image is a graphite sketch redrawn based on the original digital sketch. The star field was generated by Starry Night Pro 5.8. Click image for larger version.

Observation Notes:
Well, the weather and my schedule hasn't been cooperating too much lately for getting out under the stars with more than a pair of binoculars. Tonight, the clouds parted for a while, and the moon had yet to rise, so I took a look for Machholz at 10:30 pm. As the days go by, it keeps getting brighter. I'm still not sure how to go about estimating brightness for fuzzy things like this. But I could make out the thin ion tail with averted vision to the east-northeast, and what seemed to be a widening of the coma that would be the dust tail the south. I worked out a digital sketch over the course of 3 trips outside. I wasn't dressed for the occasion, so I didn't want to get everything put together for a pencil sketch. I worked up the sketch in Photoshop. I don't think this is the way I'd like to do things very often. It doesn't seem as precise, and it's bad for dark adaptation.

Anyway, after putting it together, I checked in Orion's The Sky, the only thing I had to fix was a slight adjustment to the position of 2 stars on the east side of the sketch. I don't know about anyone else that observes comets or asteroids, but I get a charge out of plotting its position at a specific time, and the having it confirmed neatly by the planetarium software. The position of Machholz worked out to RA 3h 53m / Dec +07� 21'. I labeled the major stars that surrounded it. Based on the angular separation of those stars, I would estimate the portion of the coma visible to me was 19' in diameter, while the ion tail extended 50'. Under direct vision I still pick up the faintest hint of green. I haven't found any recent photos of the comet to verify that I'm seeing what I think I'm seeing, so if somebody sees anything fishy about this, let me know.

Posted by Jeremy at December 30, 2004 10:30 PM .