[IAUC] IAUC 9229: C/2011 Q2; P/2011 Q3 [25139-2012/04-R1]

[quai en eps.harvard.edu]

                                                  Circular No. 9229
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
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


COMET C/2011 Q2 (McNAUGHT)
     As first announced on CBET 2797, R. H. McNaught reports his
discovery of a moderately- to strongly-condensed comet with a 0'.8
circular coma on CCD images taken with the 0.5-m Uppsala Schmidt
telescope at Siding Spring (discovery observation tabulated below);
his images from Aug. 27.4 UT show the comet with similar appearance
to that on the discovery images.  Following posting on the Minor
Planet Center's NEOCP webpage, other CCD astrometrists have also
commented on the object's cometary appearance.  Co-added images
taken by R. Holmes, T. Linder, and V. Hoette (Ashmore, IL, USA)
with a 0.41-m reflector on Aug. 28.0 reveal a coma 20" wide with a
faint tail 24" long in p.a. 138 deg.  Images taken by A. C. Gilmore
and P. M. Kilmartin with the Mount John 1.0-m reflector on Aug.
29.4 show a circular coma 12" in diameter with condensation at the
center.

     2011 UT             R.A. (2000) Decl.       Mag.   Observer
     Aug. 26.40124   13 48 16.69   -38 04 58.2   14.5   McNaught

The early astrometry was published on MPCs 75829-75830, and the
following parabolic orbital elements by G. V. Williams are from 73
observations, Aug. 26-Sept. 7:  T = 2012 Jan. 19.9372 TT, q =
1.352824 AU, Peri. = 34.5604 deg, Node = 287.3038 deg, i = 36.8904
deg (equinox 2000.0).


COMET P/2011 Q3 (McNAUGHT)
     As first announced on CBET 2803, McNaught reports his
discovery of another comet on CCD images taken with the Uppsala
Schmidt telescope (discovery observation tabulated below), the
object appearing elongated with a hint of a tail 0'.3 long in p.a.
240 deg.  His follow-up images on Aug. 30.6 UT confirm the cometary
appearance, with a tail 0'.7 long fanned between p.a. 240 and 255
deg.

     2011 UT             R.A. (2000) Decl.       Mag.   Observer
     Aug. 29.74083    0 16 50.17   - 5 53 42.4   18.5   McNaught

The early astrometry was published on MPC 75830; elliptical orbital
elements by Williams from 28 observations, Aug. 29-Sept. 4:

     T = 2011 Aug.  1.1134 TT         Peri. = 304.6632
     e = 0.548203                     Node  =  36.1778  2000.0
     q = 2.338759 AU                  Incl. =   5.9171
       a =  5.176572 AU    n = 0.0836837    P =  11.78 years

                      (C) Copyright 2011 CBAT
2011 September 12              (9229)            Daniel W. E. Green