From ndj at nickdjames.com  Sun Dec 10 22:52:01 2017
From: ndj at nickdjames.com (Nick James)
Date: Sun, 10 Dec 2017 22:52:01 +0000
Subject: [BAA Comets] 174P Echeclus outburst
Message-ID: <eedca0a1-6898-4e28-c531-19b5b2b95c52@nickdjames.com>

This Centaur is currently undergoing a significant outburst. The 
outburst was detected by Brian Skiff a couple of days ago and was 
confirmed by Jean-Francois Soulier and Richard Miles. I've received 
recent images from Denis Buczynski and Tim Haymes. There is a news item 
on the BAA website here:

https://britastro.org/node/11931

Please keep this comet under observation if you can.

Nick.

From ndj at nickdjames.com  Mon Dec 11 23:25:16 2017
From: ndj at nickdjames.com (Nick James)
Date: Mon, 11 Dec 2017 23:25:16 +0000
Subject: [BAA Comets] 174P Echeclus outburst
In-Reply-To: <eedca0a1-6898-4e28-c531-19b5b2b95c52@nickdjames.com>
References: <eedca0a1-6898-4e28-c531-19b5b2b95c52@nickdjames.com>
Message-ID: <3b237917-2977-5764-fe32-c5106e429653@nickdjames.com>

This comet is showing a nice asymmetric coma around 17 arcsec diameter 
now. Here's an image I have just taken from Chelmsford:

https://britastro.org/node/11941

Please keep observing this comet over the next few days and send us your 
images and photometry.

Thanks,

Nick.

From petercarson100 at gmail.com  Tue Dec 12 00:49:04 2017
From: petercarson100 at gmail.com (Peter Carson)
Date: Tue, 12 Dec 2017 00:49:04 -0000
Subject: [BAA Comets] 174P Echeclus outburst
In-Reply-To: <3b237917-2977-5764-fe32-c5106e429653@nickdjames.com>
References: <eedca0a1-6898-4e28-c531-19b5b2b95c52@nickdjames.com>
 <3b237917-2977-5764-fe32-c5106e429653@nickdjames.com>
Message-ID: <ED71607ED3CA4BCE8338B92432DF4AC7@peterPC>

Hi Nick,
Here's my image 90 mins ago from Southend. http://www.astromania.co.uk/174P_20171211_2305_PCarson.jpg 
The coma is definitely asymmetric.
Peter


-----Original Message----- 
From: Nick James 
Sent: Monday, December 11, 2017 11:25 PM 
To: BAA Comets discussion list 
Subject: Re: [BAA Comets] 174P Echeclus outburst 

This comet is showing a nice asymmetric coma around 17 arcsec diameter 
now. Here's an image I have just taken from Chelmsford:

https://britastro.org/node/11941

Please keep observing this comet over the next few days and send us your 
images and photometry.

Thanks,

Nick.
_______________________________________________
Comets-disc mailing list
Comets-disc at lists.britastro.org
http://lists.britastro.org/mailman/listinfo/comets-disc

From alphacentauri at tesco.net  Tue Dec 12 08:21:43 2017
From: alphacentauri at tesco.net (Andrew Robertson)
Date: Tue, 12 Dec 2017 08:21:43 -0000
Subject: [BAA Comets] 174P Echeclus outburst
In-Reply-To: <ED71607ED3CA4BCE8338B92432DF4AC7@peterPC>
References: <eedca0a1-6898-4e28-c531-19b5b2b95c52@nickdjames.com>
 <3b237917-2977-5764-fe32-c5106e429653@nickdjames.com>
 <ED71607ED3CA4BCE8338B92432DF4AC7@peterPC>
Message-ID: <000001d37322$3eec4430$bcc4cc90$@tesco.net>

It's a close call but I vote for Nick's :-)

Andrew

-----Original Message-----
From: Comets-disc [mailto:comets-disc-bounces at lists.britastro.org] On Behalf Of Peter Carson
Sent: Tuesday, December 12, 2017 12:49 AM
To: BAA Comets discussion list <comets-disc at lists.britastro.org>
Subject: Re: [BAA Comets] 174P Echeclus outburst

Hi Nick,
Here's my image 90 mins ago from Southend. http://www.astromania.co.uk/174P_20171211_2305_PCarson.jpg 
The coma is definitely asymmetric.
Peter


-----Original Message----- 
From: Nick James 
Sent: Monday, December 11, 2017 11:25 PM 
To: BAA Comets discussion list 
Subject: Re: [BAA Comets] 174P Echeclus outburst 

This comet is showing a nice asymmetric coma around 17 arcsec diameter 
now. Here's an image I have just taken from Chelmsford:

https://britastro.org/node/11941

Please keep observing this comet over the next few days and send us your 
images and photometry.

Thanks,

Nick.
_______________________________________________
Comets-disc mailing list
Comets-disc at lists.britastro.org
http://lists.britastro.org/mailman/listinfo/comets-disc
_______________________________________________
Comets-disc mailing list
Comets-disc at lists.britastro.org
http://lists.britastro.org/mailman/listinfo/comets-disc


From bunburyobservatory at hotmail.com  Tue Dec 12 11:55:49 2017
From: bunburyobservatory at hotmail.com (Jeremy Shears)
Date: Tue, 12 Dec 2017 11:55:49 +0000
Subject: [BAA Comets] Paper on "Major Outburst and Splitting of Long-Period
 Comet C/2015 ER61 (Pan-STARRS)"
Message-ID: <VI1PR01MB083022443FA82F8C4D192ED0C4340@VI1PR01MB0830.eurprd01.prod.exchangelabs.com>

by Zdenek Sekanina

https://arxiv.org/abs/1712.03197


includes amateur observations


Jeremy

From rmiles.btee at btinternet.com  Tue Dec 12 12:33:24 2017
From: rmiles.btee at btinternet.com (Richard Miles)
Date: Tue, 12 Dec 2017 12:33:24 -0000
Subject: [BAA Comets] Paper on "Major Outburst and Splitting of
	Long-Period Comet C/2015 ER61 (Pan-STARRS)"
In-Reply-To: <VI1PR01MB083022443FA82F8C4D192ED0C4340@VI1PR01MB0830.eurprd01.prod.exchangelabs.com>
References: <VI1PR01MB083022443FA82F8C4D192ED0C4340@VI1PR01MB0830.eurprd01.prod.exchangelabs.com>
Message-ID: <1DD0FA5BCFA24C9E8507B8854E7326A2@RichardPC>

Thanks Jeremy - a very comprehensive write-up but with a rather selective 
comparison with other outbursting comets, it seems. The outburst referred to 
was on 2017 April so is very recent and occurred just 36 days or so before 
perihelion (orbital period = 8.6 yr, q=1.0 au) so is a classic case of 
thermal stresses resulting in fragmentation close to perihelion.

Good to see BAA member, Erik Bryssinck being duly acknowledged following his 
discovery of the discrete fragment that was shed by its outburst. Lots of 
other amateur comet observations are referred to including Kevin Hills, Paul 
Camilleri and Michael Mattiazzo to name but a few plus a very nice set of 
colour images by Gerald Rhemann showing the comet before and after its 
outburst.

With the latest 5-mag outburst of Comet 174P, obserrvers should be watchful 
for the appearance of a long-lived fragment from that event, given it has 
been the most intense outburst since this object was discovered in 2000. 
However, the separation velocity if such a fragment exists will be of the 
order of m/s and so it may be quite a while before such a fragment appears.

Richard Miles


----- Original Message ----- 
From: "Jeremy Shears" <bunburyobservatory at hotmail.com>
To: <comets-disc at lists.britastro.org>
Sent: Tuesday, December 12, 2017 11:55 AM
Subject: [BAA Comets] Paper on "Major Outburst and Splitting of Long-Period 
Comet C/2015 ER61 (Pan-STARRS)"


> by Zdenek Sekanina
>
> https://arxiv.org/abs/1712.03197
>
>
> includes amateur observations
>
>
> Jeremy
> _______________________________________________
> Comets-disc mailing list
> Comets-disc at lists.britastro.org
> http://lists.britastro.org/mailman/listinfo/comets-disc
> 


From janicemcclean at btinternet.com  Tue Dec 12 18:06:51 2017
From: janicemcclean at btinternet.com (Janice McClean 1)
Date: Tue, 12 Dec 2017 18:06:51 +0000
Subject: [BAA Comets] Next edition of the Comet's Tale - May 2018 Call for
	Contributions
Message-ID: <E3AE12BC-E7AF-4354-8593-4F895BF99B4F@btinternet.com>

Dear All,

Firstly, many thanks to all those who contributed to the last edition.  There has been some very positive feedback.  It has also been interesting to hear how far the Tale gets emailed around the world, with messages coming back from far and wide.  Makes it all worth while.

In order to give everyone lots of time to prepare for the next one, I managed to persuade Nick and Denis to a sort of spring and autumn schedule…  We aim to produce another edition by May 2018.  Therefore, I would be very grateful for contributions by 6th April 2018.  That gives time to get over the Easter break, and is the date of the BAA Winchester weekend for those of you attending. 

I make a special plea that submissions are prepared as below.  No point in making unnecessary work for yourself:

Please use Microsoft word if possible.
Do not worry about making the submission look pretty, or using lots of headings in different fonts and different types sets etc.  I have to remove all of that in order to make a corporate look for the Tale, and will put all submissions into the same overall style.  
Do not be shy of writing in English if it is not your first language and you are not confident in writing in English.   It is not a problem for me.  I am happy to take what you send and work with that.  All I will need is your contact details to clarify points.  
I shall want a recent portrait of your handsome features to attach to your article!
Please submit images and captions separately  and not embedded in your article, as occasionally I have difficulty extracting them, especially if I do not have the same programme on my computer.  I use microsoft word for the layout.

I look forward to receiving your work at my address - janicemcclean at btinternet.com


I wish you a happy and peaceful Christmas and totally comet filled New Year.


Janice


PS I apologise if the font on this is a bit varied or peculiar, I blame the Director. 


Janice McClean
BAA Trustee and Council 
07818030786




From john_drummond at xtra.co.nz  Wed Dec 13 04:57:49 2017
From: john_drummond at xtra.co.nz (john_drummond at xtra.co.nz)
Date: Wed, 13 Dec 2017 17:57:49 +1300
Subject: [BAA Comets] 174P Echeclus outburst
In-Reply-To: <ED71607ED3CA4BCE8338B92432DF4AC7@peterPC>
References: <eedca0a1-6898-4e28-c531-19b5b2b95c52@nickdjames.com>
 <3b237917-2977-5764-fe32-c5106e429653@nickdjames.com>
 <ED71607ED3CA4BCE8338B92432DF4AC7@peterPC>
Message-ID: <381E4013380C49CFA66889EE1179538F@JohnToshibaPC>

Hi,

Here’s an image of 174P (Enchelus) from 2017 Dec 11 UT. The coma is evident and is more elongated to the south. 


http://spaceweathergallery.com/indiv_upload.php?upload_id=141227


COD E94
CON John Drummond, Possum Observatory, Patutahi, Gisborne, New Zealand [john_drummond at xtra.co.nz]
OBS J. Drummond
MEA J. Drummond
TEL 0.35-m f/10 Schmidt-Cassegrain + CCD
ACK MPCReport file updated 2017.12.13 17:38:31
AC2 john_drummond at xtra.co.nz
NET UCAC-4
0174P         C2017 12 11.45662 02 38 30.57 +11 24 05.8          14.8N      E94
0174P         C2017 12 11.45910 02 38 30.51 +11 24 05.4          14.8N      E94
0174P         C2017 12 11.46163 02 38 30.43 +11 24 04.9          14.9N      E94
----- end -----

Regards
John D, New Zealand 


From: Peter Carson 
Sent: Tuesday, December 12, 2017 1:49 PM
To: BAA Comets discussion list 
Subject: Re: [BAA Comets] 174P Echeclus outburst

Hi Nick,
Here's my image 90 mins ago from Southend. http://www.astromania.co.uk/174P_20171211_2305_PCarson.jpg 
The coma is definitely asymmetric.
Peter


-----Original Message----- 
From: Nick James 
Sent: Monday, December 11, 2017 11:25 PM 
To: BAA Comets discussion list 
Subject: Re: [BAA Comets] 174P Echeclus outburst 

This comet is showing a nice asymmetric coma around 17 arcsec diameter 
now. Here's an image I have just taken from Chelmsford:

https://britastro.org/node/11941

Please keep observing this comet over the next few days and send us your 
images and photometry.

Thanks,

Nick.
_______________________________________________
Comets-disc mailing list
Comets-disc at lists.britastro.org
http://lists.britastro.org/mailman/listinfo/comets-disc
_______________________________________________
Comets-disc mailing list
Comets-disc at lists.britastro.org
http://lists.britastro.org/mailman/listinfo/comets-disc


==============================
John Drummond, Possum Observatory, IAU Code E94, Gisborne, New Zealand (177d 53' E, 38d 38' S)
Royal Astronomical Society of New Zealand president - www.rasnz.org.nz
Gisborne Astronomical Society president - www.astrogas.co.nz
GAS Facebook - www.facebook.com/gisbornecosmos
Email: john_drummond at xtra.co.nz
Website: www.possumobservatory.co.nz
Images: http://www.possumobservatory.co.nz/latest_images-all-continuing.htm
Phone (mobile): 0275 609 287

From ndj at nickdjames.com  Sun Dec 17 11:51:25 2017
From: ndj at nickdjames.com (Nick James)
Date: Sun, 17 Dec 2017 11:51:25 +0000
Subject: [BAA Comets] 174P outburst
Message-ID: <17cb4f0e-b129-b13f-d6aa-e506fa7c5d42@nickdjames.com>

Observations by Denis Buczynski and myself (attached) with several 
different instruments show that, while the coma diameter of 174P has 
been increasing almost linearly the total magnitude has been pretty 
constant. The X axis on these plots is days from 2017 December 7.0 which 
is the probably outburst time according to Richard Miles. These 
measuredments are from unfiltered CCD observations reduced using UCAC-4 
R magnitudes.

Richard notes that, given that the coma is essentially all dust a 
constant total magnitude would be expected provided that no further 
fragmentation or albedo ageing takes place.

If you have unfiltered images of this comet between December 7 and 
December 12 I would like to receive the calibrated FITS files so that I 
can measure them in a consistent way to extract coma diameter and 
magnitude. please send them by email to the address below or, if they 
are too large for email, place them on Dropbox or something similar so 
that I can download them.

Many thanks,

Nick
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From petercarson100 at gmail.com  Sun Dec 17 21:43:06 2017
From: petercarson100 at gmail.com (Peter Carson)
Date: Sun, 17 Dec 2017 21:43:06 +0000
Subject: [BAA Comets] Comet 2016R2 billowing tail
Message-ID: <03ded562-7d65-c6cc-a469-6cbefef94741@gmail.com>

Hi All,

Comet 2016R2 PanSTARRS is behaving very oddly. Its seems to have had 
several “puffing” events and this has resulted in a broad irregular and 
knotted tail.

My image taken last night from my home observatory in Essex has captured 
some of this detail. 
http://www.astromania.co.uk/2016R2_20171217_0025_PCarson.jpg
It really needs a darker sky to do it justice.

Regards

Peter

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From buczynski8166 at btinternet.com  Mon Dec 18 01:29:44 2017
From: buczynski8166 at btinternet.com (denis buczynski)
Date: Mon, 18 Dec 2017 01:29:44 +0000 (UTC)
Subject: [BAA Comets] 174p 20171217 image
References: <1066574670.673382.1513560584302.ref@mail.yahoo.com>
Message-ID: <1066574670.673382.1513560584302@mail.yahoo.com>

Hello all,Attached is an image of Comet 174P in outburst taken this evening at Tarbatness. I understand that image attachments are now enabled in our discussion group. Ihope this image gets through.Best wishesDenis
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From john_drummond at xtra.co.nz  Mon Dec 18 03:22:22 2017
From: john_drummond at xtra.co.nz (john_drummond at xtra.co.nz)
Date: Mon, 18 Dec 2017 16:22:22 +1300
Subject: [BAA Comets] 174p 20171217 image + New image
In-Reply-To: <1066574670.673382.1513560584302@mail.yahoo.com>
References: <1066574670.673382.1513560584302.ref@mail.yahoo.com>
 <1066574670.673382.1513560584302@mail.yahoo.com>
Message-ID: <A0E08F9859D44A7FB2FF86A92FA53B46@JohnToshibaPC>

Good image Denis.

Here’s one taken from New Zealand last night – 2017 Dec 17 UT (attached). 35cm f10 SCT, STL11000M, 35 x 3 minute, Clear, 2x2. The astrometry is below - 

COD E94
CON John Drummond, Possum Observatory, Patutahi, Gisborne, New Zealand [john_drummond at xtra.co.nz]
OBS J. Drummond
MEA J. Drummond
TEL 0.35-m f/10 Schmidt-Cassegrain + CCD
ACK MPCReport file updated 2017.12.18 15:43:36
AC2 john_drummond at xtra.co.nz
NET UCAC-4
0174P        KC2017 12 17.40552 02 37 16.81 +11 19 43.3          16.0N      E94
0174P        KC2017 12 17.41310 02 37 16.58 +11 19 43.1          15.9N      E94
0174P        KC2017 12 17.42729 02 37 16.42 +11 19 42.7          15.9N      E94
0174P        KC2017 12 17.43590 02 37 16.38 +11 19 42.4          15.9N      E94
0174P        KC2017 12 17.44395 02 37 16.32 +11 19 42.3          15.9N      E94
0174P        KC2017 12 17.45238 02 37 16.14 +11 19 42.2          15.9N      E94
0174P        KC2017 12 17.46291 02 37 16.05 +11 19 41.6          15.9N      E94
0174P        KC2017 12 17.47173 02 37 15.96 +11 19 41.3          15.9N      E94
0174P        KC2017 12 17.47931 02 37 15.87 +11 19 40.9          16.0N      E94
0174P        KC2017 12 17.48814 02 37 15.78 +11 19 40.7          16.0N      E94
0174P        KC2017 12 17.49572 02 37 15.63 +11 19 40.3          16.0N      E94
----- end -----

Regards
John Drummond (E94), NZ


From: denis buczynski 
Sent: Monday, December 18, 2017 2:29 PM
To: BAA Comets Discussion List 
Subject: [BAA Comets] 174p 20171217 image

Hello all,
Attached is an image of Comet 174P in outburst taken this evening at Tarbatness. I understand that image attachments are now enabled in our discussion group. Ihope this image gets through.
Best wishes
Denis



--------------------------------------------------------------------------------
_______________________________________________
Comets-disc mailing list
Comets-disc at lists.britastro.org
http://lists.britastro.org/mailman/listinfo/comets-disc


==============================
John Drummond, Possum Observatory, IAU Code E94, Gisborne, New Zealand (177d 53' E, 38d 38' S)
Royal Astronomical Society of New Zealand president - www.rasnz.org.nz
Gisborne Astronomical Society president - www.astrogas.co.nz
GAS Facebook - www.facebook.com/gisbornecosmos
Email: john_drummond at xtra.co.nz
Website: www.possumobservatory.co.nz
Images: http://www.possumobservatory.co.nz/latest_images-all-continuing.htm
Phone (mobile): 0275 609 287
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From ndj at nickdjames.com  Mon Dec 18 08:21:47 2017
From: ndj at nickdjames.com (Nick James)
Date: Mon, 18 Dec 2017 08:21:47 +0000
Subject: [BAA Comets] 174P outburst
In-Reply-To: <17cb4f0e-b129-b13f-d6aa-e506fa7c5d42@nickdjames.com>
References: <17cb4f0e-b129-b13f-d6aa-e506fa7c5d42@nickdjames.com>
Message-ID: <f8508934-53c5-ba9f-db86-1c08f966d421@nickdjames.com>

Thanks to Eric Watkins, Peter Carson and Denis Buczynski for submitting 
their images for measurement.

The latest plots are attached.

The total magnitude since the outburst has been remarkably stable at 
around 13.55 - 13.60 (unfiltered, UCAC-4 R mags). This is measured in an 
aperture slightly larger than the detected coma diameter.

The coma diameter continues to increase. Note that the two observations 
made by Denis shortly after the outburst were either very short 
exposures (Dec 9) or when the FWHM of the coma was only around 50% 
larger than the FWHM of the stars in the image. For these two 
observations the magnitude is reliable but the coma diameter probably is 
not.

If anyone has images taken prior to December 12 and has not yet 
submitted them please send the FITS files to ndj at nickdjames.com so that 
I can include them in the analysis.

Nick James


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From ndj at nickdjames.com  Mon Dec 18 08:43:38 2017
From: ndj at nickdjames.com (Nick James)
Date: Mon, 18 Dec 2017 08:43:38 +0000
Subject: [BAA Comets] Posting attachments
Message-ID: <69381581-c808-d7ed-4830-573f24704d8a@nickdjames.com>

Morning all,

As you will have seen we have recently enabled attachments on this list 
so that it is possible to post with linked images or documents. I hope 
that this will be useful and will increase participation.

Please use this facility wisely and avoid posting huge or routine 
images. It is best to link to such images within the post. Our Section 
archive:

http://www.britastro.org/cometobs/

will still be the main way of archiving images.

Feel free to comment on this new approach and how we might best use it 
in the future.

Nick.

From bunburyobservatory at hotmail.com  Tue Dec 19 11:36:59 2017
From: bunburyobservatory at hotmail.com (Jeremy Shears)
Date: Tue, 19 Dec 2017 11:36:59 +0000
Subject: [BAA Comets] Spectroscopy and thermal modelling of the first
 interstellar object 1I/2017 U1 'Oumuamua
Message-ID: <VI1PR01MB0830CB39E5CE680149F2A6F8C40F0@VI1PR01MB0830.eurprd01.prod.exchangelabs.com>

Nature Astronomy pre-print by Alan Fitzsimmons et al. on today's arXiv: https://arxiv.org/abs/1712.06552


All the best,

Jeremy
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From bunburyobservatory at hotmail.com  Wed Dec 20 20:45:32 2017
From: bunburyobservatory at hotmail.com (Jeremy Shears)
Date: Wed, 20 Dec 2017 20:45:32 +0000
Subject: [BAA Comets] What and Whence 1I/`Oumuamua?
Message-ID: <VI1PR01MB083083FA277049B7F90A60A1C40C0@VI1PR01MB0830.eurprd01.prod.exchangelabs.com>

MNRAS submission on arXiv: https://arxiv.org/abs/1712.06721


Jeremy
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From ndj at nickdjames.com  Fri Dec 22 08:04:35 2017
From: ndj at nickdjames.com (Nick James)
Date: Fri, 22 Dec 2017 08:04:35 +0000
Subject: [BAA Comets] 174P outburst
In-Reply-To: <f8508934-53c5-ba9f-db86-1c08f966d421@nickdjames.com>
References: <17cb4f0e-b129-b13f-d6aa-e506fa7c5d42@nickdjames.com>
 <f8508934-53c5-ba9f-db86-1c08f966d421@nickdjames.com>
Message-ID: <526113b1-d0e6-e390-772a-66f1e102b3e1@nickdjames.com>

Thanks to Richard Miles, Wendy Clark, Eric Watkins, Johan Warell, Peter 
Carson and Denis Buczynski for submitting their images to the section 
for measurement.

At 15 days from the outburst the latest plots show that the coma 
continues to expand linearly at around 3.4 arcsec/day. At the comet's 
current distance of 6.6au this corresponds to an expansion velocity of 
95 m/s. The coma is now around 70 arcsec across corresponding to a 
diameter of 335,000 km at the comet.

Please keep this comet under observation. As the surface brightness of 
the coma drops long exposures will be needed to pick up its full extent.

Nick.
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From rmiles.btee at btinternet.com  Sat Dec 23 00:52:23 2017
From: rmiles.btee at btinternet.com (Richard Miles)
Date: Sat, 23 Dec 2017 00:52:23 -0000
Subject: [BAA Comets] 29P has undergone a weak outburst on Dec 21 as
	predicted !
Message-ID: <6679BD00FEBF42539A25F5B51A9A4814@RichardPC>

Our 29P/S-W1 monitoring campaign continues apace despite the poor weather in 
some parts of the world, notably the UK.

There exists a Facebook group entitled, "PACA Outbursting Comets" and the 
other day (Dec 17.75 to be precise), I posted an alert concerning 29P 
saying: ""There's a good chance of a 29P outburst in the next few days ... 
watch that space!"

I haven't sent a 29P outburst alert for a long time mainly because the 
chances of an outburst haven't been that high recently. But on this 
occasion, the currently most active/energetic site on the nucleus had not 
outburst after its last full rotation of the nucleus (each takes 57 days) 
and so the second such full rotation of this particular location coincided 
with the last few days and that meant that the cryogeyser had a good chance 
of erupting yet again. As it happens, the outburst came within 4 days of my 
prediction. Details are:

Time of outburst: 2017 12 21.52 +/-0.40
Mag change: 16.3r' to 15.3r'
Amplitude: 1.0 mag

Here are the most recent observations showing the step change in brightness, 
courtesy of Jean-Francois Soulier and myself:
0029P KC2017 12 19.71296 21 27 20.56 -12 34 04.0 16.60N A77
0029P KC2017 12 19.74962 21 27 21.94 -12 33 57.0 16.20N A77
0029P KC2017 12 19.78733 21 27 23.28 -12 33 49.9 16.41N A77
0029P C2017 12 21.01052 21 28 08.89 -12 29 41.3 16.15N W96
0029P C2017 12 21.02079 21 28 09.27 -12 29 39.2 16.24N W96
0029P C2017 12 22.00975 21 28 46.56 -12 26 17.0 15.32N W96
0029P C2017 12 22.03291 21 28 47.45 -12 26 11.4 15.40N W96
0029P C2017 12 22.05687 21 28 48.33 -12 26 07.1 15.36N W96
0029P C2017 12 22.81198 21 29 17.05 -12 23 32.4 15.18N Z21
0029P C2017 12 22.81350 21 29 17.12 -12 23 32.1 15.31N Z21

The particular region of the comet's nucleus has one or two other, less 
active sources, one of which may also erupt in response to this current 
latest outburst, so imaging the comet during the coming days is to be 
encouraged. The comet is visible low in the south-west sky shortly after 
sunset during nautical twilight. Large apertures and a CCD camera are 
required to detect the comet. It is too faint to be seen visually through 
the telescope given its low altitude from the UK (10-15 degrees) and low 
solar elongation (50 deg).

Clear skies,
Richard Miles

P.S. If anyone would like to join the PACA Outbursting Comets group then do 
get in touch.