Electronic Telegram No. 3553
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@eps.harvard.edu (alternate cbat@iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


PREDICTED POSSIBLE OUTBURST OF GAMMA DELPHINID METEORS
     P. Jenniskens, SETI Institute; and E. Lyytinen, Helsinki, Finland, predict
a return of the 1930 Gamma Delphinids meteor shower with a peak on 2013 June 11
at about 8h28m UT.  The shower is expected to last only about 30 min and
consist mainly of magnitude +2, +1, and 0 meteors.  The 1930 shower radiated
from R.A. = 313 deg, Decl. = +17 deg (equinox 2000.0); the meteors had short
trails of brief duration and were yellowish-white.  Meteor observers Paul S.
Watson, Frank Oertle, and Joseph Field of the American Meteor Society recorded
51 meteors then under full-moon conditions -- 39 of which were of magnitude +1,
and 10 of which were of magnitude 0.  The shower only lasted 30 min.  This
account is interpreted as having been caused by the dust trail of a long-
period comet, which thus is an unknown potentially hazardous comet that passed
close to earth's orbit in the previous return from which dust now streams past
the earth's orbit.  If so, that stream of dust is predicted to move into the
earth's path in 2013 -- that is, if the radiant position of the meteors was
correctly recorded in 1930 (Lyytinen and Jenniskens 2003, Icarus 32, 51-53;
Jenniskens 2006, Meteor Showers and their Parent Comets,
pp. 194 and 617).


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2013 CBAT
2013 June 10                     (CBET 3553)              Daniel W. E. Green