Electronic Telegram No. 4292
Central Bureau for Astronomical Telegrams
Mailing address:  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


JULY GAMMA DRACONID METEOR OUTBURST
     P. Jenniskens, SETI Institute and NASA Ames Research Center, reports
that stations of the CAMS meteor video camera network in the Netherlands
detected unusually strong activity from the July gamma Draconids shower
(IAU shower number 184) between July 27d23h56m and 28d00h23m UT.  According
to the data analysis by M. Breukers (Hengelo, The Netherlands), about half of
all 126 single-station-detected meteors in the partially clouded night
(typically with brightness around magnitude +2) radiated from this shower's
radiant, as did five out of nine multi-station meteors.  The median
geocentric radiant position was R.A. = 279.88 +/- 0.12 deg, Decl. = +50.12
+/- 0.46 deg (equinox J2000.0), with speed geocentric velocity 27.31 +/- 0.09
km/s, corresponding to a 1P/Halley-type comet orbit with semi-major axis 27
+/- 4 AU, q = 0.977 +/- 0.002 AU, i = 39.9 +/- 0.2 deg, Peri. = 202.7 +/-
0.5 deg, and Node = 125.133 +/- 0.007 deg (equinox J2000.0).  The parent
body is unknown.  More information is given at the following website URL:
http://cams.seti.org.
     P. Brown, University of Western Ontario, reports that the Canadian
Meteor Orbit Radar detected a strong outburst of meteors of typical magnitude
+7 from the July gamma Draconids with a full-with-at-half-maximum of about 2
hours centered on July 28d0h UT.  The observed rate translates to a peak
zenith hourly rate for a visual observer (assuming a differential mass
distribution index of 1.9) of about 50 meteors per hour for the period 0h-1h
UT on July 28.  More information is available via the following website URL:
http://fireballs.ndc.nasa.gov/cmor-radiants/.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2016 CBAT
2016 August 2                    (CBET 4292)              Daniel W. E. Green