[IAUC] CBET 2507: 20101019 : ORIONID METEORS 2010

[quai en eps.harvard.edu]

                                                  Electronic Telegram No. 2507
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 en eps.harvard.edu (alternate cbat en iau.org)
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Prepared using the Tamkin Foundation Computer Network


ORIONID METEORS 2010
     P. Jenniskens, SETI Institute, reports that the strong Orionid meteor
shower activity of 2006-2009 may repeat this year, for a final year in this
sequence, according to M. Sato and J.-I. Watanabe (2007, PASJ 59, L21);
they ascribed the 2006-2009 activity to dust trails of comet 1P/Halley that
were formed by meteoroids ejected in the years 1401 BC and 12 BC.  The
orbital evolution of the dust is affected by the 1:5 to 1:8 mean-motion
resonances with Jupiter.  This so-called "filament" component is expected
to be in the earth's path again around Oct. 20-25 in 2010, giving rise to
a higher-than-normal Orionid-shower activity that is relatively rich in
bright meteors. Sato expects a peak ZHR of 40-50 /h, at the same level
as in 2009. As case studies, Sato calculated peak times of Oct. 21 9h UT
for the 1266 BC dust trail and Oct. 25 4h UT for the 911 BC trail, both
having dust survive in the 1:6 resonance with Jupiter.


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                         (C) Copyright 2010 CBAT
2010 October 19                  (CBET 2507)              Michael Rudenko