[IAUC] CBET 1538: 20081013 : SUPERNOVA 2008gg

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                                                  Electronic Telegram No. 1538
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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CBAT en CFA.HARVARD.EDU (science)
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SUPERNOVA 2008gg
     Further to CBET 1526, A. J. Drake reports, on behalf of his colleagues,
the discovery of an apparent supernova (mag 16.3) on an unfiltered Catalina
Sky Survey (CSS) image taken on Oct. 9.31 UT, giving the position of the new
object as R.A. = 1h25m23s.0, Decl. = -18o10'20" (equinox 2000.0); nothing was
visible at this position on a CSS image from 2007 Nov. 11 (limiting mag 19.5).
T. Kryachko, Kazan State University Astrotel Observatory, Karachay-Cherkessia,
Russia; and S. Korotkiy, Ka-Dar Observatory, write that 2008gg appears at mag
16.4 on unfiltered CCD images obtained on Oct. 10.010 with a Takahashi 30-cm
f/7.8 telescope (+ Apogee Alta U9000 CCD camera), measuring its position to
be R.A. = 1h25m23s.04 +/- 0".1, Decl. = -18d10'20".8 +/- 0".1, which is about
18".7 east and 30".7 south of center of the galaxy NGC 539.  They add that
nothing is visible at this position on a Palomar Sky Survey (SERC-J) plate
obtained on 1980 Oct. 13 (via the Digitized Sky Survey; limiting mag 21.0).
Following posting on the Central Bureau's unconfirmed-objects webpage, C.
Jacques and E. Pimentel (Belo Horizonte, Brazil) report that a 60-s
unfiltered CCD image (limiting mag 17.5) taken on Oct. 13.01 with a 30-cm
f/3.3 Schmidt-Cassegrain reflector at CEAMIG-REA Observatory yields mag 16.6
and position end figures 23s.07, 20".5; they add that nothing is visible at
this position on a red DSS image from 1990 Sept. 15 (limiting magnitude 19.5).
S. Nakano, Sumoto, Japan, writes that K. Itagaki (Yamagata, Japan, 0.60-m
f/5.7 reflector) found mag 16.8 and position end figures 23s.04, 20".5 from
an unfiltered CCD image (limiting mag 18.0) taken on Oct. 13.663.


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                         (C) Copyright 2008 CBAT
2008 October 13                  (CBET 1538)              Daniel W. E. Green