[IAUC] CBET 1562: 20081107 : NEW VARIABLE STAR IN PEGASUS

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                                                  Electronic Telegram No. 1562
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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NEW VARIABLE STAR IN PEGASUS
     H. Yamaoka, Kyushu University, reports the discovery by K. Itagaki
(Yamagata, Japan) of a variable star on a survey CCD image taken with a
0.21-m f/3 reflector around Nov. 6.456 UT.  Confirmation CCD images taken on
Nov. 6.460 UT with a 0.60-m f/5.7 reflector show the variable's magnitude
to be about 13.0 and its position to be R.A. = 21h37m01.84s, Decl. =
+7d14'46".2 (equinox 2000.0).  The star was fainter than mag 17.0 on his
survey image taken on 2007 Nov. 4.485, and fainter than mag 14.5 on 2008
Oct. 13.587.  In the USNO-B1.0 star catalogue, according to Yamaoka, there
is a star with position end figures 01s.82, 46".1 and magnitudes B1 =
18.0, R1 = 16.4, B2 = 19.4, R2 = 16.8, I = 17.9; A. Henden, AAVSO notes
that the B1 and R1 magnitudes are from Palomar Sky Survey plates taken
in 1953, though the USNO-A-catalogue reductions for these same plates
yield mags 17.4 and 17.9, suggesting that all the USNO magnitudes for
this star are suspect.  In the GSC-2.3 catalogue, Yamaoka reports that the
variable has magnitudes 18.6-19.6 in the different passbands (which can
represent plates taken years apart); Henden notes that the GSC-2.2 catalogue
and the USNO-B catalogue give red mag 17.9 and 16.8, respectively, for
the variable on apparently the same Palomar Sky Survey plate.  In the
2MASS catalogue, the variable has magnitudes J = 16.5, H = 15.8, K = 15.3
(all measured nearly simultaneously).  Yamaoka and Henden both suggest
that the current outburst amplitude of about 5 mag or so suggests that
this could be a dwarf nova.  Responding a request by Yamaoka, A. Miyashita
(Seikei High School, Japan) confirmed the variable on CCD images taken
around Nov. 7.37 with a 0.15-m telescope, reporting the following
magnitudes:  Nov. 7.369, I_c = 13.29; 7.371, R_c = 14.03; 7.373, V = 13.55,
7.375, B = 13.67.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2008 CBAT
2008 November 7                  (CBET 1562)              Daniel W. E. Green