[IAUC] IAUC 8920: C/2007 X5-X15; 17P [25139-2008/05-R1]

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                                                  Circular No. 8920
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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COMETS C/2007 X5-X15 (SOHO)
     Further to IAUC 8919, additional near-sun comets have been
found on SOHO website images; all were Kreutz sungrazers except for
Meyer-group objects C/2007 X7, which were both very small and
stellar in appearance (mag about 7).  C/2007 X5 was stellar in
appearance and small (mag about 6.5) in C3 images, and slightly
diffuse with no tail in C2 images.  K. Battams describes C/2007 X6
as extremely faint (mag about 8.5), diffuse, and small.  C/2007 X8,
C/2007 X9 (which was also found by T. Hoffman), and C/2007 X12 were
tiny and stellar in appearance in C3 images (reaching mag about 7,
except C/2007 X12, which reached mag about 7.5); in C2 images, they
appeared diffuse, with C/2007 X8 appearing a little elongated and
the other two objects showing no tail.  C/2007 X10 was teardrop-
shaped and very bright (mag about 3) in C3 images, and showed a
broad head and a thin tail in C2 images.  C/2007 X11, which was
also found by H. Su, was very diffuse and faint (mag about 8).
C/2007 X13 was very diffuse, elongated, and reached mag about 7.5.
C/2007 X15 was small and diffuse (mag about 7.5).  New finder
codes:  MK = M. Kusiak; PC = P. Collison.

 Comet        2007 UT       R.A.(2000)Decl.   Inst.  F    MPEC
 C/2007 X5    Dec.  7.679   16 53.4  -26 46   C3/2   HS   2008-B36
 C/2007 X6         10.314   17 09.1  -24 44   C2     MK   2008-B45
 C/2007 X7         10.381   17 06.0  -21 50   C2     HS   2008-B45
 C/2007 X8         10.638   17 10.0  -25 31   C3/2   TH   2008-B45
 C/2007 X9         12.179   17 17.2  -25 26   C3/2   RM   2008-B45
 C/2007 X10        12.488   17 13.5  -29 42   C3/2   TH   2008-B46
 C/2007 X11        12.564   17 19.5  -24 55   C2     RK   2008-B46
 C/2007 X12        13.738   17 24.5  -25 26   C3/2   RM   2008-B46
 C/2007 X13        14.088   17 26.2  -25 04   C2     PC   2008-B46
 C/2007 X14        14.163   17 22.9  -22 10   C2     TH   2008-B48
 C/2007 X15        15.479   17 34.8  -25 02   C2     HS   2008-B48


COMET 17P/HOLMES
     Visual total-magnitude and coma-diameter estimates by A.
Pereira, Cabo da Roca, Portugal (5x22 monocular):  2007 Dec. 26.81
UT, 3.5, about 68'; 29.88, 3.6, > 65'; 2008 Jan. 1.08, 3.6, about
60'; 4.03, 3.5, about 78'; 12.03, 3.8, > 65'; 26.81, 3.8, about 80';
28.92, 4.0, about 84'; 31.95, 4.1, > 70'; Feb. 2.84, 4.3, about 70';
4.87, 4.5, about 80'; 7.97, 4.6, about 85'; 10.02, 4.6, about 90'.

                      (C) Copyright 2008 CBAT
2008 February 11               (8920)            Daniel W. E. Green