Circular No. 8361
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)
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SUPERNOVAE 2004cs, 2004ct, AND 2004cu
     Two apparent supernovae have been discovered on unfiltered CCD
images:  SNe 2004cs and 2004cu by LOSS/KAIT (via W. Li and D.
Singer; cf. IAUC 8357), and SN 2004ct by T. Boles (cf. IAUC 8343).

SN       2004 UT        R.A.  (2000.0)  Decl.   Mag.     Offset
2004cs   June 23.42   17 50 14.38  +14 16 59.5  18.0   10".4 E, 15".2 S
2004ct   June 22.01   15 43 45.75  +28 24 59.5  17.5   4".1 W, 4".4 N
2004cu   June 24.28   14 18 29.82  +12 53 03.0  18.8   27".1 E, 3".5 N

Additional approximate magnitudes, from images by the respective
discoverers unless otherwise noted:  SN 2004cs in UGC 11001, June
21.36 UT, [19.0; 24.20, 17.8.  SN 2004ct in MCG +05-37-17, Mar. 20,
[19.5; May 16, [19.5; 24.201, 17.5 (KAIT).  SN 2004cu in NGC 5550,
May 17.36, [20.0; June 12.33, 19.3 (marginal detection).  Boles
adds that SN 2004ct is not present on Digitized Sky Survey red
(1989) or blue (1993) plates.


COMET C/2003 K4 (LINEAR)
     Further to IAUC 8358, R. W. Russell, D. L. Kim, M. L. Sitko,
and W. J. Carpenter report 3-13-micron spectrophotometry of comet
C/2003 K4, obtained on June 20.3 UT at Mt. Lemmon (integration
times 90 min on the comet; reference star alpha Boo):  "A continuum,
smooth to within the signal-to-noise, was seen to rise from 3.5 to
8 microns, beyond which a weak silicate emission band may have been
observed.  An underlying blackbody continuum with a temperature of
about 235 +/- 10 K was fit to the continuum fluxes at 8.4 and 12
microns.  This grain temperature is about 22 +/- 5 percent higher
than that of an equilibrium blackbody at the comet's heliocentric
distance.  Using the same wavelength region (10.34-10.71 microns)
as for other, brighter comets in order to calculate a silicate-
feature-to-continuum ratio, the possible silicate feature was about
1.10 +/- 0.05 times higher than the continuum, with the silicate-
feature-to-continuum ratio > 1.  The comet showed the following
narrowband (about 0.25 micron) magnitudes and combined random
errors:  [8.0 microns] = 4.25 +/- 0.10; [10.5 microns] = 2.41 +/-
0.06; [12 microns] = 1.76 +/- 0.06.  Due to the low flux level of
the comet and the weakness of its silicate feature, no structure
due to crystalline material was discernible."
     Visual total-magnitude estimates:  May 12.96 UT, 10.6 (A.
Baransky, Bucha, Ukraine, 0.20-m refl.); 24.98, 9.8 (A. Diepvens,
Balen, Belgium, 0.15-m refractor); June 7.96, 8.8 (K. Hornoch,
Lelekovice, Czech Rep., 10x80 binoc.); 21.93, 8.0 (J. J. Gonzalez,
Asturias, Spain, 7x50 binoc.).

                      (C) Copyright 2004 CBAT
2004 June 24                   (8361)            Daniel W. E. Green