2023a3 20240921 johndrummond

I imaged C/2023 A3 this morning (2024 Sep 21 UT) from New Zealand with a 35cm f10 Meade SCT and SBIG STL11000M CCD. Clear filter, 10x10 second, 2x2 Bin. FoV = 35' x 23'. 

I also imaged it at the same time with an 18cm f2.8 Takahashi Epsilon Newtonian and Canon 550D. FoV = 4.1° x 2.7°. The tail extends for about 1.2° in a PA of ~251. Note the VERY subtle old 15' tail with a PA of 125° (as per Qicheng's email - pasted below). 

Both images are attached. 

Twilight was well advanced and the comet had just cleared the trees (~8-degrees altitude). There's bad vignetting and dust motes (I must update my Flats). I've applied an Unsharp Mask to try and enhance some of the tail structure with the 35cm image.