[IAUC] IAUC 9091: S/2009 S 1; 2009 UG_89; C/2009 K7-K12 [25139-2010/01-R1]

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                                                  Circular No. 9091
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS en CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
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Phone 617-495-7440/7244/7444 (for emergency use only)


S/2009 S 1
     C. C. Porco, CICLOPS, Space Science Institute, Boulder; and
the Cassini Imaging Science Team report the discovery of a
satellite orbiting within the outer B ring in Saturn's rings.  The
satellite was seen in a single Cassini narrow-angle camera image
with an exposure time of 820 ms, taken through the clear filter on
July 26 (or sixteen days before Saturn's northern vernal equinox on
Aug. 11), through the presence of a 36-km long shadow that it cast
onto the rings.  Its radial distance from the center of Saturn at
the time of the observation was measured to be 117000 km.  From the
length of its shadow and the elevation of the sun at the time of
the observation, the distance that the satellite protrudes above the
rings was measured to be approximately 150 m; the inferred diameter
of the satellite, assuming an orbit co-planar with the ring material,
is consequently approximately 300 m.


2009 UG_89
     MPEC 2009-U123 announces the discovery by the Mount Lemmon
survey of an apparently asteroidal object with a highly elliptical
orbit (e approximately 0.9) that is retrograde (i = 131 deg),
currently at Delta approximately r approximately 5 AU (with q
approximately 4.3 AU in Nov. 2010), from a 3-day arc of observation.


COMETS C/2009 K7-K12 (SOHO)
     Further to IAUC 9090, additional Kreutz sungrazers have been
found on SOHO website images.  K. Battams notes that C/2009 K7 was
small and perhaps slightly diffuse (peak mag about 7.5) in C3
images, but quite diffuse and slightly elongated in C2 images.
C/2009 K8 was tiny and stellar in appearance (mag about 8.5).
C/2009 K9 was slightly diffuse (mag about 7) in C3 images, but
quite diffuse with a short tail (and a "knot" in the tail) in C2
images.  C/2009 K10 was a "very diffuse streak" (mag about 7.5).
C/2009 K11 was stellar in appearance (mag about 6.5) in C3 images,
but slightly diffuse and fading very fast in C2 images.  C/2009 K12
was diffuse (mag about 8).

 Comet        2009 UT      R.A.(2000)Decl.   Inst.  F    MPEC
 C/2009 K7    May 20.346    3 49.1  +17 27   C3/2   BZ   2009-N50
 C/2009 K8        24.254    4 05.0  +19 04   C2     MK   2009-N50
 C/2009 K9        26.988    4 18.1  +18 31   C3/2   MU   2009-N50
 C/2009 K10       27.938    4 18.6  +19 39   C2     MU   2009-N50
 C/2009 K11       29.221    4 24.2  +18 14   C3/2   MU   2009-O18
 C/2009 K12       30.397    4 28.0  +20 02   C2     MK   2009-O18

                      (C) Copyright 2009 CBAT
2009 November 2                (9091)            Daniel W. E. Green