[BAA Comets] ATel: *possible* fragmentation of 29P

[Richard Miles]

Here's a report from the BAA Observing Campaign on 29P.

High cadence photometry shows that here have been 3 recent mini-outbursts. 
They occurred on:

2019 Sep 12.14
2019 Sep 17.70
2019 Sep 27.67

Dates are accurate to +/-0.20 days.
The first event was strongest with the inner coma magnitude rising from 
16.6R to 16.0R
The second only changed from 16.2R to 16.0R

I attach images taken on Sep 28.46 and Oct 03.65.
The former is of particularly high resolution in sub-arcsecond seeing and 
one can clearly see a fan-shaped outflow extending eastwards some 3 arcsec 
and concentrated towards p.a. 70 deg, as reported by Kelley et al.in ATel 
#13164.

We have seen similar slow-moving outflows on many occasions. Larger 
telescopes pick them up early on in their development but they can also be 
seen in images taken with smaller instruments provided that a large number 
of frames are stacked, such as shown in Jean-François Soulier's stack of 60 
frames taken on Oct 01.1, also attached. You can see the development of the 
fan structure in the eastwards direction.

Richard Miles
BAA

----- Original Message ----- 
From: "Nick James" <ndj at nickdjames.com>
To: "BAA Comets discussion list" <comets-disc at lists.britastro.org>; "Peter 
Carson" <petercarson100 at gmail.com>
Sent: Thursday, October 03, 2019 10:42 PM
Subject: Re: [BAA Comets] ATel: *possible* fragmentation of 29P


> And here's mine. The inner coma looks symmetrical to me with a brighter
> fan to the east but nothing particularly unusual. My photometry give
> about 16.05 in a 5.7 arcsec aperture so again nothing unusual.
>
> It will be interesting to see whether this turns out to be real or not.
>
> Nick.
>
>
>
>
> On 03/10/2019 23:08, Peter Carson wrote:
>> Hi David,
>> Thanks for posting a link to this report.
>> I had actually seen it earlier in the day and checked my image of 29P
>> taken last night, see attached. I'm afraid I can't see any evidence of a
>> fragmentation but my image scale is perhaps too small.
>>
>> Peter
>>
>> -----Original Message----- From: David Swan
>> Sent: Thursday, October 03, 2019 10:02 PM
>> To: BAA Comets discussion list
>> Subject: [BAA Comets] ATel: *possible* fragmentation of 29P
>>
>> http://www.astronomerstelegram.org/?read=13164
>>
>>
>>
>> _______________________________________________
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