[IAUC] IAUC 9001: C/2008 X1; C/2008 O7 [25139-2009/08-R1]

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                                                  Circular No. 9001
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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COMET C/2008 X1 (HILL)
     R. E. Hill reports his discovery of a comet on Catalina Sky
Survey CCD images obtained with the 0.68-m Schmidt reflector
(discovery observation tabulated below), the comet noted from co-
added exposures as has having a nuclear condensation of size 8"-10"
with a diffuse coma of diameter 30" and a broad, diffuse tail 15"-
20" long in p.a. 290-300 deg.  Four additional co-added 60-s
exposures by Hill on Dec. 5.2 UT in 2"-4" seeing show a similar
appearance, with the nuclear condensation measured as 10"-12"
across.  Following posting on the Minor Planet Center's 'NEOCP'
webpage, other CCD observers have noted the object's cometary
appearance.  R. Ligustri (Talmassons, Udine, Italy), observing
remotely with a 0.25-m f/3.4 reflector near Mayhill, NM, U.S.A.,
finds a coma diameter of about 25" on twelve co-added 180-s
exposures taken on Dec. 5.3; using the same instrumentation, E.
Guido, G. Sostero, and P. Camilleri report that 24 co-added 120-s
unfiltered exposures from Dec. 5.4 show a compact inner coma about
10" in diameter, and an extremely faint, fan-shaped, broad tail
about 30" long toward the northwest.  R. A. Kowalski (Mt. Lemmon
1.5-m reflector, Dec. 5.37) reports a coma approximately 12" in
diameter and a very faint, low-contrast, fan-shaped tail in p.a.
290 deg.

     2008 UT             R.A. (2000) Decl.       Mag.
     Dec.  4.34227    5 24 20.26   + 3 17 52.2   17.4

The available astrometry, the following preliminary parabolic
orbital elements, and an ephemeris appear on MPEC 2008-X42.

     T = 2009 May  20.504 TT          Peri. =  44.947
                                      Node  = 108.322   2000.0
     q = 1.61769 AU                   Incl. =  23.774


COMET C/2008 O7 (SOHO)
     Further to IAUC 8987, below are tabulated the discovery data
for an additional near-sun presumed comet found on SOHO website
images.  Not a member of any known dynamical group, C/2008 O7 was
very diffuse and perhaps slightly elongated (mag about 7.5-8.0);
based on its appearance, K. Battams remarks that it is unlikely to
have survived.

 Comet       2008 UT       R.A.(2000)Decl.   Inst.  F    MPEC
 C/2008 O7   July 18.921    7 54.6  +19 12   C2     BZ   2008-T10

                      (C) Copyright 2008 CBAT
2008 December 5                (9001)            Daniel W. E. Green