The latest lightcurves for 12P/Pons-Brooks and C/2023 A3
(Tsuchinshan-ATLAS) are attached to this email. Both comets are southern
hemisphere objects now.

12P is fading as it it moves out from perihelion. Coverage is still a
bit patchy but no outbursts have been detected since the large one on
June 10. If you are observing this comet please consider measuring it to
contribute to the lightcurve. Details of how to do this are here:

https://britastro.org/section_news_item/12p-pons-brooks-observing-campaign

C/2023 A3 is now brightening rapidly as it sinks into the southern
hemisphere evening twilight and we'll probably lose it from iTelescope
in the next few days. It is currently looking very healthy and
astrometry up to today shows no sign of any systematic residuals in a
purely gravitational orbit solution so absolutely no indication of any
fragmentation.

The comet has been visible in the STEREO HI1 instrument for the last few
days. I have put some daily timelapses here:

https://nickdjames.com/Comets/2024/2023A3/STEREO/

The comet is visible as a very small object with a tail pointing left
and moving to the right and downwards in the bottom left corner of the
images. It is *not* the prominent comet-like object on the left edge of
the frame. This is a flare from Venus which is the very bright object
with an associated column overload on the right of the image.

Nick.