[IAUC] CBET 1518: 20080927 : ORIONID METEORS 2008

[IAUC mailing list]

                                                  Electronic Telegram No. 1518
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS en CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT en CFA.HARVARD.EDU (science)
URL http://www.cfa.harvard.edu/iau/cbat.html


ORIONID METEORS 2008
     P. Jenniskens, SETI Institute, reports that last year's strong activity
of the Orionid meteor shower on Oct. 20.4-24.2 UT (cf. CBET 1108) may
continue into 2008 and 2009, according to M. Sato and J.-I. Watanabe (PASJ
59, L21); they ascribed the 2007 activity to dust trails of comet 1P/Halley
that were formed by meteoroids ejected in the years -1265, -1197, and -910.
The orbital evolution is affected by the 1:6 mean-motion resonance with
Jupiter.  This so-called "filament" is expected to be in the earth's path
again around Oct. 18-24 in 2008 and again in 2009, giving rise to a higher-
than-normal Orionid-shower activity that is relatively rich in bright
meteors.  M. Sato (National Astronomical Observatory of Japan, Tokyo)
predicts an encounter with the -1265 dust trail in the period 2h13m-8h08m
UT on 2008 Oct. 19, peaking earlier than in 2007.  The approach distance is
slightly larger than in 2007, which could result in lower peak rates.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2008 CBAT
2008 September 27                (CBET 1518)              Daniel W. E. Green