Electronic Telegram No. 3249
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director:  Daniel W. E. Green; Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
e-mail:  cbatiau@eps.harvard.edu (alternate cbat@iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


DRACONID METEORS 2012
     Peter Brown, Department of Physics and Astronomy, University of Western
Ontario, writes that real-time radar observations by the Canadian Meteor Orbit
Radar (CMOR) have detected a very strong probable outburst of the Draconid
meteor shower, beginning near 16 UT on Oct. 8.  This strong activity, noticed
by Quanzhi Ye of the Western Meteor Group, shows up exceptionally strong on
radiant plots made over the last few hours and is much more visible to the
radar than the 2011 outburst.  The collecting area of the radar for the shower
is also much larger than in 2011 (as of 16 UT), so some of this increased
intensity is due to better viewing conditions.  He notes, however, that the
intensity of the increase is almost certainly consistent with a very strong
outburst.
     More detailed analysis of the CMOR radar fluxes from the shower show
noticeable activity beginning near 12 UT on Oct. 8 (solar longitude 195.43
deg) with ZHRs around 50 meteors/hr, building over the next few hours to an
extremely high ZHR estimated to be > 1000 meteors/hr between 16h and 17h UT
on Oct. 8 (solar longitude 195.62 deg).  The flux appears to have decreased
over the next two hours, until by 18h.5 UT the ZHR was at a level of only a
few hundred and steadily decreasing.  Due to the radiant geometry with
respect to the radar, CMOR can no longer detect significant flux from the
shower after about 19h.5 UT.  Brown adds:  "These values and analysis remain
rough, and the ZHR values could easily be wrong by a factor of several, as
we have no direct estimate of the particle population index (which critically
affects the ZHR or flux estimate for a shower such as this), but I think
there is no question a very strong shower (or even a storm) has been
(or is) occurring."


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2012 CBAT
2012 October 8                   (CBET 3249)              Daniel W. E. Green