Electronic Telegram No. 4127
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


POTENTIAL METEOR SHOWER FROM COMET C/2015 D4 (BORISOV)
      P. Jenniskens, SETI Institute and Ames Research Center, NASA; E.
Lyytinen, Helsinki, Finland; and C. Bemer, Boran sur Oise, France, report
that long-period comet C/2015 D4 (cf. CBET 4071; P around 560 yr) has no
known associated annual meteor shower but may be responsible for periodic
meteor outbursts from its 1-revolution dust trail veering into the earth's
path when the earth passes by the ascending node.  While approaching the
sun, the comet passes the ecliptic plane just outside of Jupiter's orbit,
which results in strong periodic perturbations of the trail position near
the earth's orbit.  When the dust trail is in the earth's path at the right
time, meteors are expected to radiate for about one hour from geocentric
R.A. = 79 deg, Decl. = -32 deg, with geocentric velocity 45.9 km/s.  The
position of the 1-revolution dust trail was calculated between 1990 and
2050 AD and, based on the comet orbit calculated from 32 observations
between 2015 Feb. 23 and Apr. 10 (cf. MPEC 2015-H37), meteor showers are
expected in 2017 and 2029.  However, a better comet orbit is required to
make reliable predictions.  Observers are encouraged to submit astrometric
data for this comet.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2015 CBAT
2015 July 30                     (CBET 4127)              Daniel W. E. Green