[BAA Comets] Recovery of lost Comet 72P

[denis buczynski]

Lost Comet 72P Denning-Fujikawa recovered.

     H. Sato, Tokyo, Japan, reports his recovery of the long-lost comet 72D,
which was lost between 1881 and 1978 (cf. IAUC 3300), and again since 1978.
Sato's CCD images obtained with an iTelescope 0.43-m f/6.8 astrograph (+
luminance filter) at Siding on June 17.8 UT show the comet to be moderately
condensed with a coma 25" in diameter; his confirming images taken with
an iTelescope 0.51-m f/6.8 astrograph at Siding Spring on June 18.8 also show
the comet to be moderately condensed with a coma 25" in diameter in poor
weather conditions, and no tail was imaged in twenty stacked 20-s exposures.
The comet's w-band magnitude was measured both nights within a circular
aperture of radius 13".  Sato's astrometry is tabulated below.

     2014 UT             R.A. (2000) Decl.       Mag.   Observer
     June 17.82268    2 23 11.69   + 6 51 08.4          Sato
          17.82448    2 23 12.29   + 6 51 12.7            "
          17.82627    2 23 12.95   + 6 51 15.9   16.8     "
          18.80404    2 28 41.31   + 7 30 08.5            "
          18.80662    2 28 42.17   + 7 30 14.3   16.3     "

The indicated correction to the prediction by S. Nakano (ICQ 2013 Comet
Handbook, p. H10) is Delta(T) = +0.24 day.  The comet had missed returns to
perihelion on 1987 Aug. 2, 1996 May 29, and 2005 June 20.  The following
linked orbital elements by Nakano are from 43 observations spanning 1881-2014
(mean residual 1".4; non-gravitational parameters A_1 = -0.15, A_2 =
+0.0241).  Additional orbital elements and an ephemeris by G. V. Williams
appear on MPEC 2014-M11.

                    Epoch = 2014 July  2.0 TT
     T = 2014 July 11.62965 TT        Peri. = 337.84103
     e = 0.8190854                    Node  =  36.11683 2000.0
     q = 0.7841539 AU                 Incl. =   9.16957
       a =  4.3343877 AU   n = 0.10922258   P =   9.02 years

(C) Copyright 2014 CBAT
2014 June 19                     (CBET 3908)              Daniel W. E. Green


For an overview of the history of observations of this comet go to Gary Kronk's Cometography page at this link:

http://cometography.com/pcomets/072p.html



Denis Buczynski
Secretary Comet Section
British Astronomical Association