IAU Electronic Telegram No. 4497

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 F2 = P/2005 JN (SPACEWATCH)
     E. Schwab, Egelsbach, Germany, reports the recovery of comet P/2005 JN
(cf. IAUC 8528) on CCD images obtained on Mar. 17 by P. Ruiz with a 1.0-m
f/4.4 reflector at the European Space Agency's Optical Ground Station,
Tenerife, Spain, with measurement assistance by M. Micheli, D. Koschny, A.
Knoefel, and M. Busch.  The comet showed no coma and no tail on frames with
a total exposure time of 600 s.  Schwab obtained confirming observations on
Mar. 21 remotely with a 0.8-m f/3 Schmidt reflector at Calar Alto, Spain;
again, the comet showed no coma and no tail on frames with a total exposure
time of 600 s.  The astrometry is tabulated below, together with additional
observations obtained on Mar. 17 by A. D. Grauer with the Mt. Lemmon 1.5-m
reflector and identified by G. V. Williams at the Minor Planet Center.

     2018 UT             R.A. (2000) Decl.       Mag.   Observer
     Mar. 17.18191   12 55 41.11   + 8 48 42.0   20.2   Ruiz
          17.18945   12 55 40.81   + 8 48 43.6   20.1     "
          17.19699   12 55 40.51   + 8 48 45.8   20.1     "
          17.20454   12 55 40.22   + 8 48 47.6   20.0     "
          17.34493   12 55 35.33   + 8 49 23.7   20.6   Grauer
          17.35009   12 55 35.11   + 8 49 25.0   20.4     "
          17.35524   12 55 34.89   + 8 49 26.4   20.5     "
          17.36040   12 55 34.75   + 8 49 28.0   20.7     "
          21.91090   12 52 38.24   + 9 08 22.4   19.7   Schwab
          21.92041   12 52 37.91   + 9 08 24.9   19.8     "
          21.93003   12 52 37.46   + 9 08 26.8   19.6     "

The indicated correction to the prediction by Williams on MPC 96480 is
Delta(T) = -1.00 day.  The comet was missed at its 2012 return to perihelion.
The following linked orbital elements by Williams (from 33 observation
spanning 2005 Apr. 4-2018 Mar. 21; mean residual 0".4) and an updated
ephemeris appear on MPEC 2018-F85.

                    Epoch = 2005 July  9.0 TT
     T = 2005 June 20.10761 TT        Peri. = 153.56275
     e = 0.3491122                    Node  =  70.79322 2000.0
     q = 2.2762877 AU                 Incl. =   8.85878
       a =  3.4972043 AU   n = 0.15070323   P =   6.54 years

                    Epoch = 2011 Dec. 25.0 TT
     T = 2012 Jan.  5.18710 TT        Peri. = 153.48151
     e = 0.3473483                    Node  =  70.78292 2000.0
     q = 2.2864838 AU                 Incl. =   8.85239
       a =  3.5033750 AU   n = 0.15030525   P =   6.56 years

                    Epoch = 2018 July 21.0 TT
     T = 2018 July 21.83160 TT        Peri. = 153.33157
     e = 0.3490943                    Node  =  70.75806 2000.0
     q = 2.2777781 AU                 Incl. =   8.85933
       a =  3.4993983 AU   n = 0.15056153   P =   6.55 years


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

                         (C) Copyright 2018 CBAT
2018 March 22                    (CBET 4497)              Daniel W. E. Green