Vern’s Weblog

I had some minor difficulties locating comet Lovejoy just before 5 am this morning. The scope goto accuracy wasn’t as good as usual. I decided to realign on Vega and Altair as the stars I originally used had already set or just about to. Once done the scope’s precision goto was accurate again.

Images acquired with Celestron Nexstar 11 telescope, F3.3 focal reducer, and Stellacam2 video camera.

Temperature was 20°F, 0-3 mph wind, transparency good, and turbulence 5/10.

Comet C/2006P1 (McNaught) from earlier this evening shortly after sunset. I’ve tried finding it both in the morning and the evenings during the past week and failed until this evening. It is actually quite bright. Mike and I could both see it naked eye (barely) this evening around 5:20pm. I didn’t realize a comet could be both a morning and evening object on the same day, but this comet is. The sun and the comet are nearly the same right ascension (within 5′) and the comet is about 12 degrees further north in altitude. Thus the comet just barely manages to appear before sunrise and after sunset. A clear view of the western (or eastern) horizon is necessary to see this comet. For us in Colorado right now it is only about 6 degrees above the horizon when it becomes visible 20-30 minutes after sunset. Also, depending how near you are to the foothills to the west you may lose much of that. I increased my search time window this evening by about 15 minutes by setting up on a hill in Broomfield about 10 miles east of here.

Image taken from Broomfield, CO at at 5:28pm MST with Stellarvue A1010 80mm refractor telescope and Canon Xti camera. (1/5th sec shutter at ASA 800 — slightly overexposed). Single image cropped and brightness reduced with Photoshop, noise filtered. I got to the site late and didn’t have time to setup notebook to check focus and exposure. Settings were close but not as good as they should have been. Image taken 2 minutes before it disappeared behind the foothils. Some blur due to poor focus and some due to tracking. Maybe I’ll get another try tomorrow before yet another blizzard moves into our area on Thursday.

Periodic comet P/2006 HR30 (Siding Spring) is currently in the constellation Cygnus. As you can see in the below image it is quite “asteroid-like” in appearance.  I’m now not surprised that we couldn’t find it last week visually as we were looking for the customary nebulous head. Even though it is nearly directly overhead shortly after sunset, it is quite faint, vmag estimate is 13.9.

Images taken from Louisville, CO on Nov 26, 2006 between 17:59 MST to 18:04 MST and 18:15 MST to 18:19 MST. Telescope was Celestron Nexstar11, F3.3 focal reducer, and Astrovid Stellacam II video camera. Images were dark subtracted and flat field corrected with ImagePlus, aligned and stacked with Registax4.

Comet C/2006 L2 was low, thin clouds in the area, and the sky was already brightening when these images were taken. Not to mention that the comet is also quite dim (vmag 13), so these images are quite poor. Image was discovered by Robert McNaught at the Siding Spring near earth object survey on June 14, 2006.

Images taken at 05:42 to 05:44, 05:44 to 05:46, and 05:58 to 06:00 from Louisville, CO with Celestron Nexstar 11 telescope, F3.3 focal reducer, and Astrovid Stellacam II video camera. Integrate 128 frames (4 sec), medium gamma, and 9/14 gain. Images were dark subtracted and flat field corrected with ImagePlus. Aligned and stacked with Registax4.

Comet C/2006 L1 Garradd is currently in constellation Leo. Brightness estimate is near vmag 9 and it should continue to brighten slightly for the next couple months.  It was discovered in June 4, 2006 by Gordan Garradd as part of the Siding Spring Survey search for near earth objects .

Images taken from Louisville, CO at 05:30 to 05:32 and 05:54 to 05:56 MST with Celestron Nexstar 11 telescope, Meade F3.3 focal reducer, and Astrovid Stellacam II video camera. Gain set at 9/14, medium gamma, and integrate 128 frames (4 sec).  Dark subtracted and flat field corrected with ImagePlus, stacked and aligned with Registax4.