IAU Electronic Telegram No. 4552

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)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network

COMET P/2018 R1 = P/2001 R6 (LINEAR-SKIFF)
     E. Schwab, Egelsbach, Germany, reports the recovery of comet P/2001 R6
(cf. IAUC 7723) on CCD images obtained by D. Abreu with a 1.0-m f/4.4
reflector at the European Space Agency's Optical Ground Station, Tenerife
(astrometry tabulated below).  The comet shows no coma and no tail on stacked
images with 600 s total exposure time.  Assisting in the measurements were
M. Micheli, D. Koschny, A. Knoefel, and M. Busch.

     2018 UT             R.A. (2000) Decl.       Mag.   Observer
     Sept. 7.08501    2 08 16.55   -13 25 56.0   19.8   Abreu
           7.14283    2 08 16.67   -13 26 02.4   19.8     "
           7.20030    2 08 16.83   -13 26 08.6   19.9     "
           8.11194    2 08 20.48   -13 27 49.1   19.1     "
           8.21684    2 08 20.60   -13 28 00.4   20.0     "

The indicated correction to the prediction by G. V. Williams on MPEC 2013-A29
is Delta(T) = +0.36 day.  The following linked orbital elements (including
elements at the missed 2010 return to perihelion) by Williams from 95
observations spanning 2001 Aug. 19-2018 Sept. 8 (mean residual 0".6) and an
ephemeris appear on MPEC 2018-R59.

                    Epoch = 2010 Mar. 25.0 TT
     T = 2010 Mar. 26.34015 TT        Peri. = 308.45182
     e = 0.4776943                    Node  =  67.32340 2000.0
     q = 2.1786419 AU                 Incl. =  17.38669
       a =  4.1712010 AU   n = 0.11569441   P =   8.52 years

                    Epoch = 2018 Oct.  9.0 TT
     T = 2018 Oct.  4.58710 TT        Peri. = 308.47883
     e = 0.4759541                    Node  =  67.33485 2000.0
     q = 2.1910673 AU                 Incl. =  17.37964
       a =  4.1810600 AU   n = 0.11528544   P =   8.55 years


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2018 CBAT
2018 September 8                 (CBET 4552)              Daniel W. E. Green