[IAUC] CBET 2147: 20100126 : URSID METEORS 2009

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                                                  Electronic Telegram No. 2147
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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URSID METEORS 2009
     P. Jenniskens, SETI Institute, reports significant Ursid shower activity
over normal annual rates over the period 2009 Dec. 22d00h-22d15h UT.  Pierre
Martin at Ottawa, Canada, reported seeing a -5 magnitude Ursid at 6h00m UT,
which left a 15-s persistent train.  Visual observations starting at 7h30m UT
gave apparent rates of 10-15 Ursids/hr under 6.3-magnitude skies.  Both Ilkka
Yrjola at Kuusankoski, Finland, and Esko Lyytinen at Helsinki, Finland,
measured elevated rates using the technique of meteor forward scattering.
>From their data, the outburst peaked at Dec. 22d09h +/- 0.5 hr UT (solar
longitude = 270.51 +/- 0.02 deg, equinox 2000.0), with a full-width-at-half-
maximum of 6 +/- 1 hr.  The shower was rich in overdense echoes.  The
outburst was due to the 'filament' dust component of comet 8P/Tuttle, the
encounter of which was predicted at Dec. 22d06h UT with FWHM = 8.2 hr
(Jenniskens 2006, *Meteor Showers and their Parent Comets*, p. 645).


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2010 January 26                  (CBET 2147)              Daniel W. E. Green