Electronic Telegram No. 4296
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


2016 PERSEID METEORS
     P. Jenniskens, SETI Institute and NASA Ames Research Center, reports
that the predicted encounters with the 1-revolution and 4-revolution dust
trails of comet 109P/Swift-Tuttle were observed (cf. CBET 4293).  There is
also evidence that the Perseid Filament was encountered.  The shower is
ongoing.
     Preliminary results from single-station video observations of the 2016
Perseid shower by the International Meteor Organization (IMO) Video Network
between Aug. 11d21h and Aug. 12d04h UTC, analyzed by G. Barentsen (Ames
Research Center, NASA) and S. Molau (IMO), show that activity from both the
1-revolution and 4-revolution dust trail crossings manifested as,
respectively, a 1-hr full-width-at-half-maximum wide peak of zenith hourly
rate of 140 Perseids per hour centered on Aug. 12d22h49m UTC (solar
longitude 139.446 deg, equinox J2000.0) and a narrow 26-min-wide peak of
ZHR = 190 Perseids/hr centered on Aug. 12d23h22m UTC (139.468 deg).
Activity of the background annual Perseid shower was higher by perhaps
20 percent over 2012 rates.
     Observing from La Palma, C. Johannink, K. Jobse, S. Dijkstra, C. ter
Kuile, F. Bettonvil, and T. Wieland confirm from visual observations the
maximum being around about Aug. 11d23h30m UTC, but also noticed a flurry of
meteors of magnitude 0 to -2 around Aug. 12d02h15m UTC (139.58 deg) and
in a period starting at 4h UTC (139.65 deg).  For more visual observations
posted in real time, see URL http://www.imo.net/live/perseids2016/.
     Jenniskens and M. Koop, observing visually in moonlight from Fremont
Peak Observatory (California), did not detect the predicted older
7-revolution dust trail crossing at Aug. 12d04h43m UTC, but did record high
Perseid rates centered at Aug. 12d08h10m UTC (139.820 deg), which may have
been the return of the Perseid Filament.
     Japanese radio forward-meteor-scatter observations, in a live tally
administered by H. Sugimoto, confirm the narrow peak centered on Aug. 11 at
23h20m UTC; they also observed a broad peak with rates above 2015 Perseid
activity centered around 139.8 deg (see information posted at website URL
http://www5f.biglobe.ne.jp/~hro/Flash/2016/PER/index.html).


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2016 CBAT
2016 August 13                   (CBET 4296)              Daniel W. E. Green