[IAUC] IAUC 9059: COMET C/2009 O4 (HILL); C/2009 D5, C/2009 D6 [25139-2009/08-R1]

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                                                  Circular No. 9059
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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COMET C/2009 O4 (HILL)
     R. E. Hill reports his discovery of another comet on CCD
images taken with the Catalina 0.68-m Schmidt telescope (discovery
observation tabulated below); he notes that four stacked 20-s
exposures in 2" seeing show the object to have a bright, nuclear
condensation of size 15" x 20" that is elongated northwest-
southeast, with no coma and a broad, diffuse tail about 2' long
in p.a. 300 deg.  After posting on the Minor Planet Center's
'NEOCP' webpage, other cometary astrometrists have noted the
object's cometary appearance.  Y. Ikari (Moriyama, Shiga-Ken,
Japan, 0.26-m reflector, July 30.7 UT) reports coma diameter 0'.3
and a tail 0'.6 long in p.a. 315 deg.  F. Fratev (Zvezdno
Obshtestvo Observatory, Plana, Bulgaria, 0.35-m reflector, July
31.0) writes that sixty stacked 40-s unfiltered exposures reveal a
coma nearly 28" in diameter and a tail about 1'.5 long in p.a. 320
deg.  J. A. Henriquez (Tenerife, Spain, 0.2-m reflector, July 31.1;
poor weather conditions) measures an 11" coma and a 14".5 tail in
p.a. 317 deg.  J. E. McGaha (Tucson, AZ, U.S.A., 0.36-m reflector,
July 31.3) notes that six stacked 60-s images show an 8" bright
round coma with a fan-shaped tail 35" long at p.a. 315 deg.  W. H.
Ryan (Magdalena Ridge 2.4-m reflector, July 31.35-31.38) notes a
tail at p.a. about 290 deg.  G. Hug (Scranton, KS, U.S.A., 0.56-m
reflector, July 31.4) reports a short, broad tail in p.a. about
310 deg.

     2009 UT             R.A. (2000) Decl.       Mag.   Observer
     July 30.37424    0 33 09.91   + 7 38 01.8   16.3   Hill

The available astrometry, the following preliminary parabolic
orbital elements by B. G. Marsden, and an ephemeris appear on MPEC
2009-O56.

     T = 2009 Dec.  1.451 TT          Peri. = 210.640
                                      Node  = 173.459   2000.0
     q = 2.86118 AU                   Incl. =  94.583


COMETS C/2009 D5 AND C/2009 D6 (SOHO)
     Further to IAUC 9058, starlike apparent comets have been found
on SOHO website images:  C/2009 D5 was a Kreutz object (mag about
6.5-7), while Meyer-group member C/2009 D6 was slightly elongated
(mag about 7).

 Comet        2009 UT       R.A.(2000)Decl.   Inst.  F    MPEC
 C/2009 D5    Feb. 23.679   22 48.1  -10 41   C3     MK   2009-M55
 C/2009 D6         24.814   22 37.2  - 7 26   C2     RK   2009-M55

                      (C) Copyright 2009 CBAT
2009 July 31                   (9059)            Daniel W. E. Green