Electronic Telegram No. 3766
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


COMET P/2013 Y1 = P/2002 AR_2 (LINEAR)
     J. V. Scotti, Lunar and Planetary Laboratory, University of Arizona,
reports his recovery of comet P/2002 AR_2 (cf. IAUC 7869) on CCD images taken
on Dec. 25 with the Spacewatch 1.8-m telescope (+ Finger Lakes Instruments
ProLine Model PL3041-LC camera + Schott OG-515 filter), with the comet showing
a 9" coma that is slightly asymmetric around the center of the nuclear region,
but with no obvious tail.  Following Scotti's report, G. V. Williams found
additional pre-recovery observations made by Scotti on Sept. 14 (0.9-m f/3
reflector at Kitt Peak) and at Mount Lemmon on Sept. 24 (R. E. Hill) and Oct.
9 (E. J. Christensen).  The observations are tabulated below and indicate a
correction to the prediction by B. G. Marsden on MPC 75742 of Delta(T) = -0.72
day, and to the prediction by S. Nakano in the 2013 Comet Handbook of Delta(T)
= -0.71 day.

     2013 UT             R.A. (2000) Decl.       Mag.   Observer
     Sept.14.22026    0 33 51.68   + 0 19 58.6   21.1   Scotti
          14.24137    0 33 50.65   + 0 20 00.2   20.8     "
          14.25648    0 33 49.83   + 0 20 03.4   20.9     "
          24.37214    0 24 55.17   + 0 33 29.2   20.3   Hill
          24.37740    0 24 54.85   + 0 33 29.5   20.2     "
          24.38269    0 24 54.51   + 0 33 30.1   20.1     "
          24.38796    0 24 54.20   + 0 33 29.8   19.6     "
     Oct.  9.20091    0 10 24.06   + 0 55 31.8   20.3   Christensen
           9.20753    0 10 23.65   + 0 55 32.6   20.1     "
           9.21416    0 10 23.28   + 0 55 33.4   20.2     "
           9.22083    0 10 22.84   + 0 55 34.1   19.7     "
           9.28006    0 10 19.30   + 0 55 40.4   20.1     "
           9.28265    0 10 19.11   + 0 55 40.5   19.8     "
           9.28524    0 10 18.98   + 0 55 40.8   20.0     "
           9.28783    0 10 18.83   + 0 55 41.2   20.1     "
     Dec. 25.14955   23 55 52.63   + 7 54 01.9   20.6   Scotti
          25.15633   23 55 52.93   + 7 54 06.0   20.8     "
          25.16315   23 55 53.24   + 7 54 10.1   20.4     "

The following linked orbital elements by Williams (from 54 observations
spanning 2002 Jan. 6-2013 Dec. 25; mean residual 0".5) and residuals
appear on MPEC 2013-Y30.

                    Epoch = 2014 May  23.0 TT
     T = 2014 May  14.71599 TT        Peri. =  73.40521
     e = 0.6164363                    Node  =   7.66803 2000.0
     q = 2.0485964 AU                 Incl. =  21.10451
       a =  5.3409541 AU   n = 0.07985016   P =  12.34 years


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

                         (C) Copyright 2013 CBAT
2013 December 25                 (CBET 3766)              Daniel W. E. Green