Jonathan,

I get a total magnitude of 8.8 in photometric radius of 2 arcmin using
comphot and 11.5 in a 9 arcsec radius this morning. The outburst won't
affect the total magnitude very much.

I measure the bright outburst dust coma diameter as:

Jan 18.776	18 arcsec
Jan 19.256	40 arcsec

That implies that the outburst happened sometime around Jan 18.39 (09:20
UTC yesterday). My latest non-outburst observation is Jan 18.263 which
is consistent with this.

If anyone has any images taken between Jan 18.26 and Jan 18.75 please
let me know.

The inner coma this morning shows the characteristic 12P outburst shape
with "horns" and a dark lane in PA 80 deg.

Nick.

On 18/01/2024 18:53, Jonathan Shanklin - BAS - jdsh at bas.ac.uk (via
baa-comet list) wrote:
> I've just observed it visually - I did wonder if it was in outburst as it was much more strongly condensed and easier to see than a couple of days ago. Not that much brighter though at mag 8.5
>
>
> Regards,
>
> Jonathan Shanklin
> BAA Comet Section visual observations co-ordinator
> https://www.ast.cam.ac.uk/~jds/