[IAUC] IAUC 9199: P/2011 C2; C/2008 P7 [25139-2011/04-R1]

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                                                  Circular No. 9199
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 P/2011 C2 (GIBBS)
     A. R. Gibbs, Lunar and Planetary Laboratory (LPL), reports his
discovery of a comet (discovery observation tabulated below) on CCD
images taken with the 1.5-m reflector at Mount Lemmon; he notes
that his initial four co-added 30-s images show a compact coma of
size 5" x 6", elongated in the direction of the tail, which itself
is 8" long in p.a. 295 deg.  Four co-added 60-s follow-up exposures
taken by Gibbs on Feb. 12.39 UT show a 14" tail in p.a. 290 deg;
the tail is also evident on Gibbs' image from Feb. 13.4.  After
posting on the Minor Planet Center's 'NEOCP' webpage, other CCD
astrometrists have commented on the object's cometary appearance.
K. Sarneczky writes that his unfiltered images taken on Feb. 14.9
with the Konkoly Observatory's 0.60-m Schmidt telescope
(Piszkesteto, Hungary) show a 6" coma and a 10" tail in p.a. 285
deg.  J. V. Scotti, LPL, reports that images taken on Feb. 15.3
with the Spacewatch 1.8-m f/2.7 reflector show the comet to be
slightly diffuse with a coma diameter of about 4" and a subtle
tail extending 0'.11 in p.a. 288 deg.  S. Foglia and T. Vorobjov
report that they measured a 6" round coma on eighty stacked 60-s
exposures taken by R. Holmes (Ashmore, IL, U.S.A., 0.61-m f/4
astrograph) on Feb. 15.3.

     2011 UT             R.A. (2000) Decl.       Mag.   Observer
     Feb. 12.29235   10 02 51.93   +22 29 28.5   19.9   Gibbs

The available astrometry (including prediscovery Mt. Lemmon
observations of Jan. 30), the following elliptical orbital elements
by G. V. Williams, and an ephemeris appear on MPEC 2011-C97.

     T = 2012 Jan. 16.5860 TT         Peri. = 161.4083
     e = 0.270794                     Node  =  12.1984  2000.0
     q = 5.377605 AU                  Incl. =  10.9111
       a =  7.374598 AU    n = 0.0492149    P =  20.0 years


COMET C/2008 P7 (SOHO)
     Further to IAUCs 9198, another presumed Kreutz sungrazer
(stellar in appearance; peak mag about 7) has been found by J.
Ruan on SOHO website images (initial observation tabulated below).
Astrometric measures were made by K. Battams, reductions were done
by M. Rudenko, and orbital calculations were done by B. G. Marsden
(cf. MPEC 2010-T38).

 Comet        2008 UT       R.A.(2000)Decl.   Inst.  F    MPEC
 C/2008 P7    Aug.  7.179    8 54.2  +14 49   C3    JR   2010-T38

                      (C) Copyright 2011 CBAT
2011 February 15               (9199)            Daniel W. E. Green