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IAUC number

                                                  Circular No. 8946
Central Bureau for Astronomical Telegrams
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
URL http://www.cfa.harvard.edu/iau/cbat.html  ISSN 0081-0304
Phone 617-495-7440/7244/7444 (for emergency use only)

     L. A. G. Monard, Pretoria, South Africa, reports his discovery
of a variable object (mag 14.2) on unfiltered CCD images taken on
May 14.14 UT, the object located at R.A. = 0h54m34s.16, Decl. =
-37o38'28".6, which is 227" west and 153" north of the core of the
Sculptor-group galaxy NGC 300.  Nothing is visible at this position
on a red Digitized Sky Survey image (limiting mag about 20.5).
Additional approximate magnitudes for the variable from Monard's
earlier images:  2007 Dec. 30.8, [18.5; 2008 Feb. 8.75, [18.0; Apr.
17.1, [15.5; 24.16, 16.5; May 15.14, 14.2.
     Following posting of this object on the Central Bureau's
unconfirmed-objects webpage, H. E. Bond, Space Telescope Science
Institute; F. M. Walter, Stony Brook University; and J. Velasquez,
Cerro Tololo Interamerican Observatory, report that a spectrum
(resolution 1.72 nm), obtained on May 15.4 UT with the SMARTS 1.5-m
telescope at Cerro Tololo, shows emission lines of H_alpha, H_beta,
the Ca II triplet at 854.2, 849.8, and 866.2 nm, and -- remarkably
-- strong emission at the forbidden [Ca II] doublet at 729.1 and
732.3 nm.  Ca II H and K are seen in absorption.  The Balmer lines
are only slightly resolved at the velocity resolution (790 km/s) of
the spectra.  The mean heliocentric radial velocity of the features
is about +430 km/s, probably consistent with membership in NGC 300.
At an optical absolute magnitude of -12.5, the object is
photometrically and spectroscopically not a classical nova,
luminous blue variable, or supernova.  The spectrum is fairly
similar to that of V838 Mon on 2002 Feb. 13 (Wisniewski et al. 2003,
Ap.J. 588, 486, Fig. 5) -- an object suggested to represent the
collision or merger of two stars.  Continued spectroscopic and
photometric monitoring of this transient in NGC 300 is urged.

     Improved parabolic orbital elements for this comet (cf. IAUC 8940)
from MPEC 2008-J55:

     T = 2008 July 13.387 TT          Peri. =  68.253
                                      Node  = 273.511   2000.0
     q = 1.72402 AU                   Incl. =  61.854

                      (C) Copyright 2008 CBAT
2008 May 16                    (8946)            Daniel W. E. Green

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