Circular No. 8560
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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CBAT@CFA.HARVARD.EDU (science)
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COMET P/2005 N2 (HERGENROTHER)
     D. Herald, Kambah (near Canberra, A.C.T.), reports his 
recovery of comet P/1998 W2 on CCD images obtained with a 0.36-m 
f/3.9 Schmidt-Cassegrain reflector on July 4 and 5 (with astrometry, 
the following orbital elements, and an ephemeris published on MPEC
2005-N28).  Herald notes that stacking fifteen 5-min frames shows a 
tail of length approximately 20" in p.a. 270 deg.  The indicated 
correction to the predictions on MPC 45658 and in the 2005 Comet 
Handbook is Delta(T) = +0.27 day.

                    Epoch = 2005 Nov.  6.0 TT
     T = 2005 Nov.  2.4811 TT         Peri. =  13.8784
     e = 0.607511                     Node  = 356.5030  2000.0
     q = 1.425773 AU                  Incl. =  21.8941
       a =  3.632648 AU    n = 0.1423538    P =   6.924 years


COMET C/2005 N3 (LARSON)
     S. Larson reports his discovery of a comet (discovery
observation given below) on CCD images taken in the course of the 
Mt. Lemmon Survey, the object showing a 4" coma and a 10" tail in 
p.a. 230 deg on July 5.4 UT.  R. H. McNaught obtained confirming 
CCD images with the 1.0-m f/8 reflector at Siding Spring on July 
5.6 that show a condensation merging into a tail 15" long in p.a. 
240 deg.

     2005 UT             R.A. (2000) Decl.       Mag.
     July  5.38079   21 23 26.08   -14 08 44.7   20.2

The astrometry (including prediscovery observations from Mount 
Lemmon on July 3.4), the following preliminary parabolic orbital 
elements, and an ephemeris appear on MPEC 2005-N29.  The comet is 
quite likely to be of short period.

     T = 2005 Dec. 18.860 TT          Peri. =  98.198
                                      Node  = 300.859   2000.0
     q = 1.25088 AU                   Incl. =   8.243


COMET 21P/GIACOBINI-ZINNER
     Total visual magnitude estimates by J. J. Gonzalez (Leon, 
Spain, 0.20-m reflector):  May 18.12 UT, 11.2; June 2.09, 10.5; 
6.11, 10.2; July 3.11, 9.4.

                      (C) Copyright 2005 CBAT
2005 July 5                    (8560)            Daniel W. E. Green