[BAA Comets] 29P S-W 1: Predictions update (was possible start of outburst ?)

[Richard Miles]

Good morning, Jean-François / Jean-Gabriel,

Since my earlier alert I have finished my analysis of 29P's outburst 
behaviour having found something unexpected in the meantime, which has 
changed things a little. The job is now finished and it is only now a matter 
of writing the results up for publication!

The outbursts from each active site are subject to a stochastic process and 
usually require several revolutions before they can re-outburst.
That means any one prediction may or may not happen. However, the timing 
accuracy of a prediction is now better at +/-2.5 days.
I can also estimate how strong an outburst will happen - not sure how good 
this part of the prediction is.

Each active site has a different probability of outburst, so here are my 
finished predictions:

2014 Feb 27.6  (15% strong)
2014 Mar 11.5  (5% very weak)
2014 Mar 22.0  (2% weak)
2014 Mar 28.5 (25% strong)

So there you have it.

Although any one site may not go into outburst it may be possible to detect 
some low level of activity around these dates.
My definition of an outburst used in the analysis is a brightness increase 
of 2 magnitudes or more: that is with a measuring aperture of 10 arcsec 
across or thereabouts.

Cheers,
Richard Miles
British Astronomical Association


----- Original Message ----- 
From: "Soulier Jean-François" <jeffcomete at yahoo.com>
To: <amaury at spaceobs.com>; <comets-ml at yahoogroups.com>; 
<Jean-Gabriel.Bosch at unige.ch>; <jeffcomete at yahoo.com>; 
<rmiles.btee at btinternet.com>
Sent: Thursday, February 27, 2014 9:14 AM
Subject: 29P S-W 1 possible start of outburst ?


Good morning.

JG Bosch observed comet 29P on 20140226.27 with the CAO T400RC Remote 
Telescope, SpaceObs., A.Maury, Chile
and found an abnormal activity.
After image processing, the measures seem unfortunately distorted by many 
layers of stars with the measuring
aperture to used to measure the comet. Maybe therefore unreliable.
Since we were in doubt, we took observing time on CAO. This morning and it 
seems that comet 29P is really in wake-up phase (?).
Indeed, since June 13 2013, which is the last recorded by the CAO station 
W96, comet 29P has not gone any brighter than mag : 17.4

In 20140227.179 we note a m2 of 16.9 (+/-0.2). R.O. : 5.52"
In 20140227.323 we note a m2 of 16.8 (+/-0.2). R.O. : 5.52"
Echant. : 0.69"/pix
No troublesome star in the field of measuring aperture (reference image DSS) 
radius.

http://6888comete.free.fr/images/forum/courbe29P1.jpg

http://6888comete.free.fr/images/forum/courbe29P2.jpg

http://6888comete.free.fr/images/forum/29P20140224.jpg

http://6888comete.free.fr/images/forum/29P20140227A.jpg

http://6888comete.free.fr/images/forum/29P20140227B.jpg

Please find the first image that possible early outburst, but also
the two curves Site observers comets French shows activity 29P from 2013 to 
the present.
http://comet.observations.free.fr/all-obs-table.php?Code=0029P&y1=1908&m1=01

So we are still in doubt. Currently we are still following it for another 1 
hours ...Can other stations confirm ?
Thank you for your comments and feedback comments on this "possible start of 
outburst" of 29P S-W1.

Cordially.
SOULIER Jean-François / BOSCH Jean-Gabriel
C10/W96/France