IAU Electronic Telegram No. 4253

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 P/2016 A9 = P/2008 Y2 (GIBBS)
     E. Schwab, Egelsbach, Germany; and M. Micheli report the recovery of
comet P/2008 Y2 (cf. IAUC 9008).  CCD images obtained by P. Ruiz on Jan.
10.3 UT with a 1.0-m f/4.4 reflector of the European Space Agency's Optical
Ground Station at Tenerife show no coma, but a 10" tail is visible in p.a.
302 degrees (measured by Schwab, Micheli, D. Koschny, A. Knoefel, and M.
Busch).  Micheli adds that a confirming observation was obtained by J. S.
Silva, D. Lazzaro, F. Monteiro, R. Souza, and T. Rodrigues on Jan. 12.2 with a
1.0-m f/7 reflector at the Observatorio Astronomico do Sertao de Itaparica at
Nova Itacuruba, Pernambuco, Brazil, with no details about appearance provided.

     2016 UT             R.A. (2000) Decl.       Mag.   Observer
     Jan. 10.25737   13 23 51.09   -11 43 47.4   20.1   Ruiz
          10.26494   13 23 51.81   -11 43 54.2   20.0     "
          10.27252   13 23 52.52   -11 44 01.1   19.7     "
          12.23047   13 27 00.39   -12 13 12.2   20.7   Silva

The indicated correction to the prediction by G. V. Williams on MPC 79351 is
Delta(T) = -0.02 day.  The indicated correction to the prediction by S. Nakano
in the ICQ's 2015 Comet Handbook is Delta(T) = -0.01 day.  The astrometry,
the following linked orbital elements by Williams (from 346 observations
spanning 2008 Dec. 1-2009 Apr. 30; mean residual 0".4), and an ephemeris
appear on MPEC 2016-C42.

                    Epoch = 2015 Oct. 25.0 TT
     T = 2015 Nov.  5.95886 TT        Peri. = 162.33601
     e = 0.5450632                    Node  = 330.86325 2000.0
     q = 1.6294078 AU                 Incl. =   7.28788
       a =  3.5816135 AU   n = 0.14540723   P =   6.78 years


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2016 CBAT
2016 February 6                  (CBET 4253)              Daniel W. E. Green