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IAUC 8401: S/2004 S 3, S/2004 S 4,, R/2004 S 1; 2004eg, 2004eh,, 2004ei

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                                                  Circular No. 8401
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT@CFA.HARVARD.EDU (science)
URL http://cfa-www.harvard.edu/iau/cbat.html  ISSN 0081-0304
Phone 617-495-7440/7244/7444 (for emergency use only)


S/2004 S 3, S/2004 S 4, AND R/2004 S 1
     C. C. Porco, CICLOPS, Space Science Institute, Boulder; and
the Cassini Imaging Science Team (cf. IAUC 8389) report the
discovery of two objects, S/2004 S 3 and S/2004 S 4, orbiting
within the F ring of Saturn.  S/2004 S 3 orbits just outside the
outer strand of the F ring, interior to the orbit of Saturn XVII
(Pandora), the outer F-ring shepherd.  S/2004 S 4 orbits within the
inner F ring strand.  S/2004 S 3 was observed in an imaging
sequence specifically designed to search for new satellites in the
F-ring region and consisting of 19 narrow-angle-camera clear-filter
images taken over 2.3 hr on June 21.  S/2004 S 4 was observed in a
sequence designed to study the photometric behavior of Saturn's
rings taken five hours later and consisting of four narrow-angle-
camera images taken 40 s apart in the green, red, blue, and near-
infrared broadband filters (Porco et al. 2004, Space Sci. Rev., in
press).  A low-residual single orbit that crosses the F ring can be
fitted to the motions of both objects, but dynamical considerations
currently make it unclear whether these objects are one and the
same body, and whether they are satellites or clumps.  If
satellites, the objects are approximately 4-5 km across.  Also, a
new ring of diffuse material, R/2004 S 1, has been seen in Cassini
images of the F-ring region in the same orbit as the satellite
Saturn XV (Atlas).


SUPERNOVAE 2004eg, 2004eh, AND 2004ei
     Three apparent new supernovae have been discovered on CCD
images taken by J. Young (2004eg; Table Mountain 0.6-m f/16
reflector + R and I filters) and by T. Boles (2004eh and 2004ei;
cf. IAUC 8399).

SN       2004 UT        R.A.  (2000.0)  Decl.    Mag.     Offset
2004eg   Sept. 1.488   4 28 08.26  +21 39 18.3   19.5   20" W, 1".4 S
2004eh   Sept. 8.003   2 26 11.82  +27 36 24.1   17.1   7".8 W, 11".6 N
2004ei   Sept. 8.074   3 41 32.69  +37 13 30.2   17.9   4".3 E, 2".9 S

Approximate unfiltered CCD magnitudes from the respective
discoverers (plus LOSS/KAIT magnitudes by W. Li, who independently
found SN 2004eg):  SN 2004eg in UGC 3053, Feb. 5.12, [20.0 (Li);
Aug. 20.48, 18.4 (Li); Sept. 1.497, I = 19.0; 2.409, R = 19.5;
6.45, 18.6 (Li); 8.445, R = 19.5.  SN 2004eh in UGC 1892, 2003 Oct.
19, [19.5; Nov. 27, [19.5; 2004 Sept. 9.001, 18.5.  SN 2004ei in
UGC 2817, Jan. 9, [19.5; Feb. 22, [19.5; Sept. 8.998, 17.9.  None
of the new objects is present on Sky Survey images dating to
1988-1991 (limiting red mag 20.8-21.5; limiting blue mag 21.5-22.5).

                      (C) Copyright 2004 CBAT
2004 September 9               (8401)            Daniel W. E. Green

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