Electronic Telegram No. 4267
Central Bureau for Astronomical Telegrams
Mailing address:  Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
e-mail:  cbatiau@eps.harvard.edu (alternate cbat@iau.org)
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Prepared using the Tamkin Foundation Computer Network


COMET 252P/LINEAR
     P. Jenniskens, SETI Institute and NASA Ames Research Center; and J.
Vaubaillon, Institut de Mecanique Celeste et de Calcul des Ephemerides, Paris,
report that, in the wake of the close 0.0356-AU approach of comet 252P to the
earth on Mar. 21 (cf. CBET 4259), it is possible that a new meteor shower will
appear on Mar. 28 and 29.  A standard model was developed by integrating the
orbit of the comet back to A.D. 1850 and ejecting dust at each perihelion
passage since that time.  After forward-integrating these particles to Mar.
2016, it was found that at no time this year are the densest dust trail
sections in the earth's path.  Instead, a diffuse cloud of perturbed
meteoroids ejected during 1894-1926 is calculated to be in the earth's path
during solar longitude 7.5-8.9 degrees (peak at 8.15 deg; equinox J2000.0),
between Mar. 28.0 and 29.417 UT.  Dust ejected in 1921 is predicted to peak
around solar lonitudes 8.01 and 8.47 deg (Mar. 28.5 and 28.958 UT,
respectively), while dust from 1915 would peak at 8.27 deg (Mar. 28.75).
Slow meteors will radiate from a geocentric radiant at R.A. = 77.0 deg,
Decl. = -16.3 deg, with velocity V_g = 11.1 km/s.  Rates will be low.
     Selected total-magnitude and coma-diameter estimates for comet 252P,
visual unless noted otherwise:  Jan. 24.51 UT, 17.5, -- (K. Kadota, Ageo,
Japan, 0.25-m reflector + CCD); Feb. 10.48, 16.2, 0'.4 (K. Yoshimoto,
Yamaguchi, Japan, 0.16-m reflector + CCD); 27.47, 15.5, -- (Kadota); Mar.
5.84, 10.5, 5' (J. J. Gonzalez, Leon, Spain, 0.20-m reflector); 6.47, 11.3,
8' (D. A. J. Seargent, Cowra, NSW, Australia, 25-cm reflector); 8.46, 9.5,
15' (M. Mattiazzo, Swan Hill, Australia, 25x100 binoculars); 11.02, 8.6, 12'
(M. Goiato, Aracatuba, Brazil, 20x100 binoculars); 11.46, 8.0, 25'
(Mattiazzo, 8x40 binoculars); 13.50, 7.0, 30' (Mattiazzo); 14.06, 6.6, 30'
(Goiato, 7x50 binoculars); 15.44, 6.1, 40' (Mattiazzo; moonlight); 16.14,
6.1, 35' (Goiato).


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2016 CBAT
2016 March 17                    (CBET 4267)              Daniel W. E. Green