[IAUC] IAUC 9230: C/2011 Q4; C/2011 R1 [25139-2012/04-R1]

[quai en eps.harvard.edu]

                                                  Circular No. 9230
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
New postal address:  Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
CBATIAU en EPS.HARVARD.EDU           ISSN 0081-0304
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Prepared using the Tamkin Foundation Computer Network


COMET C/2011 Q4 (SWAN)
     As first announced on CBET 2809, a possible comet visible on
SOHO SWAN spacecraft ultraviolet images was reported by V. Bezugly
(Dnepropetrovsk, Ukraine) and by R. D. Matson (Irvine, CA, U.S.A.).
The first approximate SWAN position given below is by Bezugly,
while the last one is by Matson, and they reflect the poor
resolution of the SWAN images.  R. H. McNaught's confirming images
on Sept. 4 were obtained with the 0.5-m Uppsala Schmidt telescope,
showing a large, strongly condensed, 3'.0 circular coma.  Bezugly
notified M. Mattiazzo (Castlemaine, Vic., Australia) of his find,
and Mattiazzo obtained CCD images with a Canon 300D camera (+
300-mm-f.l. telephoto lens) showing the comet at mag about 11.5.

     2011 UT             R.A. (2000) Decl.       Mag.   Observer
     Aug. 23.1       14 09         -33 04               SWAN
     Sept. 1.5       14 13.7       -23 57                 "
           4.38224   14 13 08.69   -21 54 29.1   12.6   McNaught
           4.38436   14 13 08.70   -21 54 23.8   13.1     "

The initial astrometry appears on MPEC 2011-R22.  The following
parabolic orbital elements by G. V. Williams are from 24
observations, Sept. 4-7:  T = 2011 Sept. 20.7674 TT, q = 1.122335
AU, Peri. = 1.5526 deg, Node = 251.7758 deg, i = 147.4363 deg
(equinox 2000.0).


COMET C/2011 R1 (McNAUGHT)
     As first announced on CBET 2810, R. H. McNaught reports his
discovery of another comet on CCD images taken with the 0.5-m
Uppsala Schmidt telescope (discovery observation tabulated below),
the object showing a basically circular coma about 12" across,
possibly elongated toward the northwest with a suggestion of a tail
about 0'.2 long toward the northwest; the comet is strongly
condensed.  After posting on the Minor Planet Center's NEOCP
webpage, P. Birtwhistle reported a slightly cometary appearance, as
well, from his images taken on Sept. 5.1 UT with a 0.40-m reflector.

     2011 UT             R.A. (2000) Decl.       Mag.   Observer
     Sept. 3.71539    3 02 39.74   -15 10 18.8   16.5   McNaught

The early astrometry was published on MPCs 75830-75831; parabolic
orbital elements by Williams from 28 observations, Aug. 29-Sept. 4:
T = 2012 Oct. 27.3599 TT, q = 2.232780 AU, Peri. = 305.7334 deg,
Node = 221.4637 deg, i = 116.0908 deg (equinox 2000.0).

                      (C) Copyright 2011 CBAT
2011 September 12              (9230)            Daniel W. E. Green