[IAUC] IAUC 9026: C/2009 E1 [25139-2009/08-R1]

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                                                  Circular No. 9026
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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COMET C/2009 E1 (ITAGAKI)
     H. Yamaoka, Kyushu University, reports the discovery of a
comet with coma diameter about 70" on CCD images taken by Koichi
Itagaki (Yamagata, Japan) with a 21-cm f/3 reflector (diameter of
field 2.2 deg) located at Takanezawa, Tochigi, Japan, using
software by H. Kaneda (Sapporo, Japan) to detect moving objects
automatically.  The original times for the two discovery images (as
well as the first four follow-up images taken at the same location
with a 30-cm f/7.8 reflector) were later corrected and relayed by
S. Nakano (Sumoto, Japan) and are tabulated below; they were
measured by Kaneda.  Nakano adds that the comet is diffuse with
weak condensation and a hint of tail toward the south, measuring
total mag 11.9 from an image taken on Mar. 14.424 UT.

     2009 UT             R.A. (2000) Decl.       Mag.   Observer
     Mar. 14.41509    2 48 07.10   + 8 23 31.0   12.8   Itagaki
          14.41522    2 48 06.88   + 8 23 33.3   12.8     "
          14.42556    2 48 05.43   + 8 24 19.4            "
          14.42872    2 48 05.06   + 8 24 34.2            "
          14.43199    2 48 04.57   + 8 24 47.3            "
          14.44446    2 48 02.82   + 8 25 45.6            "

     Available CCD astrometry, including that sent to the Central
Bureau after posting on the Minor Planet Center's NEOCP webpage,
was published on CBET 1721, with most of the astrometrists
reporting on the object's cometary appearance:  R. Holmes
(Charleston, IL, USA, 0.61-m f/4.5 astrograph; measurer H. Devore;
Mar. 15.0) reports that ten co-added exposures reveal a nuclear
condensation 28" in diameter and a diffuse coma 54".8 in diameter
with no tail.  E. Guido, G. Sostero, and P. Camilleri (observing
remotely with a 0.25-m f/3.4 reflector near Mayhill, NM, USA; Mar.
15.12) write that thirty co-added 30-s unfiltered exposures show a
bright inner coma with diameter of about 1'.4, and a faint external
halo nearly 4' in diameter (total mag about 11.0).  J. E. McGaha
(Tucson, AZ, USA, 0.36-m f/10 reflector, Mar. 15.4) relates that
fifteen stacked 30-s images show a 42"-diameter bright coma with a
fan-shaped tail spanning 60 deg (90" long at p.a. 70 deg, the
center of the fan); red magnitudes from single 30-s exposures
within specific photometric apertures:  30", 14.1; 60", 13.1; 90",
12.2; 180", 11.3.  K. Kadota (Ageo, Saitama-ken, Japan, 0.25-m f/5
reflector; Mar. 15.41) reports a bright coma of diameter 3'.8 and
total mag 10.8, with strong central condensation and no tail.

                      (C) Copyright 2009 CBAT
2009 March 15                  (9026)            Daniel W. E. Green