Lorenzo Comolli's Astronomy HomePage

Comet Atlas G3 was my first comet to be observed in full daylight, at midday, at 6° from the Sun. It was a real surprise. On 12 Jan 2025 at 11.54 UT (12.54 local time) I pointed the telescope to the Sun using an Astrosolar filter. After synching the mount, I swifted to the comet's coordinates 6° from the Sun, removed the solar filter and - WOW- the comet was visible with a small tail right in the fild center! I used a TEC 140 apo refractor on a Gemini G41 mount with FS2 drive and a ZWO ASI6200MM camera. Exposure of 5 ms with R filter, average of 1000 frames.

I also tried to image the comet at sunrise the next day, 13 Jan 2025 7.25 UT. However due to my horizon and to the comet at only 5° elongation from Sun, I imaged the comet when the Sun was already rised and was at 3° above horizon, even if hidden by far buildings. The resulting image was nearly the same as the midday imagin of the day before. Similar exposure time of 1 ms with L filter because of the bright sky.

I was very lucky also to have my daylight image published on Spaceweather homepage on 13 Jan 2025, see screenshot below.

Technical Data
Optics	TEC 140
Focal Length	1011 mm
Focal Ratio	f/7.2
Exposure Time	1000 x 5 ms R filter at 10.3 fps with ROI 1600x1200 pix
CCD	ASI 6200 MM used in software binning 2x2
Chip temperature	-10°C
Location	Tradate, VA, Italy, at 305 m height
Date	12 January 2025 h11.54 UT
Mount	Gemini G41
Temperature and humidity	T=~5°C, RH=~50%
Notes	See description at the top of the page.

Technical Data
Optics	TEC 140
Focal Length	1011 mm
Focal Ratio	f/7.2
Exposure Time	1000 x 1 ms L filter at 8 fps with ROI 2392x1596 pix
CCD	ASI 6200 MM used in software binning 2x2
Chip temperature	-20°C
Location	Tradate, VA, Italy, at 305 m height
Date	13 January 2025 h7.25 UT
Mount	Gemini G41
Temperature and humidity	T=-5°C, RH=95%
Notes	See description at the top of the page.