[IAUC] IAUC 9095: C/2009 W1; V496 Sct [25139-2010/01-R1]

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                                                  Circular No. 9095
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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COMET C/2009 W1 (HILL)
     R. E. Hill, Lunar and Planetary Laboratory, reports his
discovery of a comet (discovery observation tabulated below) on CCD
images taken with the 0.68-m Schmidt telescope in the course of the
Catalina Sky Survey; three co-added 30-s exposures in 4"-5" seeing
show a small nuclear condensation 7"-8" across with a diffuse,
faint tail 20"-30" long in p.a. about 300 deg.  Four co-added 40-s
exposures in 2"-3" seeing by Hill on Nov. 19.4 UT show a nuclear
condensation 4"-5" across with a 1"-2" coma and a tail 20"-30" long
and 10"-12" wide in p.a. about 300 deg.  After posting on the Minor
Planet Center's 'NEOCP' webpage, other CCD astrometrists have also
noted the object's cometary appearance.  F. Fratev, Sofia, Bulgaria,
reports that twenty-one stacked 40-s CCD exposures obtained with a
0.35-m reflector at Plana, Bulgaria, on Nov. 19.1 shows a diffuse
coma nearly 10" in diameter and a tail about 60" long in p.a. 275
deg.  G. Hug (Scranton, KS, U.S.A., 0.56-m reflector, Nov. 19.5)
notes a condensed nuclear condensation and a short, diffuse tail
20" long in p.a. 290 deg.  A. R. Gibbs (Mt. Lemmon 1.5-m reflector,
Nov. 19.5) writes that four co-added 60-s unfiltered CCD images
taken in good seeing show a bright, diffuse coma of size 5" x 7"
with a 30" tail in p.a. 290 deg whose width is constant and equal
to the coma diameter.  D. Chestnov, Moscow, reports that five
stacked 300-s unfiltered CCD exposures taken by T. Kryachko and B.
Satovski with a 0.3-m reflector at the Zelenchukskaya Station of
Engelhardt Observatory on Nov. 19.04 show a tiny coma and a 0'.2
tail in p.a. 285 deg.

     2009 UT             R.A. (2000) Decl.       Mag.   Observer
     Nov. 18.50653    9 46 17.11   +28 51 20.0   18.5   Hill

The available astrometry, the following very preliminary parabolic
orbital elements, and an ephemeris appear on MPEC 2009-W34; the
true orbit may well be of short period.

     T = 2009 June 26.570 TT          Peri. =  18.783
                                      Node  =  54.349   2000.0
     q = 2.46594 AU                   Incl. =  14.418


V496 SCUTI
     Visual magnitude estimates (cf. IAUC 9093):  Nov. 14.724 UT,
7.6 (P. Schmeer, Bischmisheim, Germany); 18.719, 7.2 (Schmeer);
18.722, 7.3 (K. Hornoch, Vohancice, Czech Republic).

                      (C) Copyright 2009 CBAT
2009 November 19               (9095)            Daniel W. E. Green