[IAUC] IAUC 9169: P/2010 R2; C/1997 C2 [25139-2011/04-R1]

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                                                  Circular No. 9169
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 P/2010 R2 (LA SAGRA)
     Jaime Nomen, Barcelona, Spain, writes that careful examination
of an object detected at the La Sagra Observatory in Spain on Sept.
14.9 UT (0.45-m f/2.8 reflector, discovery position tabulated below)
shows some diffuse structure -- an appearance confirmed on Sept.
16.0 as a north-south elongation with some coma extending about 8"
in p.a. 185 deg.  Following a suggestion by B. G. Marsden that the
same object had already been recorded at La Sagra on Aug. 13.0,
Nomen also examined those images, but with no conclusive result
about the appearance.  After posting of the object on the 'NEOCP'
webpage, P. Birtwhistle (Great Shefford, Berkshire, England, 0.40-m
f/6 Schmidt-Cassegrain reflector) remarked that on Sept. 17.0 the
object had a strongly condensed coma of diameter 6" and a tail 6"
wide and 11" long in p.a. 190 deg.  On Sept. 17.1, R. Holmes
(Westfield, Illinois, 0.61-m f/4.5 astrograph) obtained images
showing a 5" coma and a 15" tail in p.a. 165 deg (measured by S.
Foglia, Novara Veveri, Italy), and on Sept. 17.2, J. V. Scotti
(Spacewatch 1.8-m reflector) described the object as of stellar
appearance, with an obvious tail to the south.  G. Sostero,
Povoletto, Italy, writes that twelve stacked 300-s unfiltered CCD
images that he took with E. Guido, L. Donato, and V. Gonano
remotely using a 0.15-m f/7.3 refractor at the Tzec Maun
Observatory (near Moorook, Australia) on Sept. 17.6 show a
condensed coma nearly 10" in diameter.

    2010 UT             R.A. (2000) Decl.       Mag.
    Sept. 14.86552   22 22 00.40   +25 30 48.6   18.4

Further astrometry are given on MPEC 2010-S11 and 2010-S28, with
the following orbital elements taken from the latter.  The object
appears to be another "main-belt comet", similar to 133P = (7968)
Elst-Pizarro.

     T = 2010 June 25.0979 TT         Peri. =  59.3696
     e = 0.153778                     Node  = 270.7569  2000.0
     q = 2.622922 AU                  Incl. =  21.3991
       a =  3.099569 AU    n = 0.1806143    P =   5.457 years


COMET C/1997 C2 (SOHO)
     Further to IAUC 9168, an additional Kreutz sungrazer was found
on SOHO website images, stellar in appearance with peak mag about 7.

 Comet        2009 UT       R.A.(2000)Decl.   Inst.  F    MPEC
 C/1997 C2    Feb. 2.990    21 26.3  -17 35   C3    MK   2010-O33

                      (C) Copyright 2010 CBAT
2010 September 20              (9169)            Daniel W. E. Green