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IAUC 4782: GS 2023+338; OJ 287; P/GUNN; PU Vul

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                                                  Circular No. 4782
Central Bureau for Astronomical Telegrams
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Telephone 617-495-7244/7440/7444 (for emergency use only)
TWX 710-320-6842 ASTROGRAM CAM     EASYLINK 62794505

GS 2023+338
     F. Makino and the Ginga Team, Institute of Space and
Astronautical Science, Sagamihara, Kanagawa, telex: "A bright x-ray
nova was discovered with the all-sky monitor aboard the Ginga
satellite on May 22 at R.A. = 20 23.3, Decl. = +33 50' (equinox 1950.0).
The corners of the error box are at 20 23.7, +34 02'; 20 24.1,
+33 58'; 20 22.9, +33 40'; and 20 22.5, +33 43'.  On May 23 the x-ray
intensity observed with the large area counters varied over the range
0.1-1.2 Crab.  The x-ray spectrum is very hard, and the intensity
exhibited erratic variations at various timescales longer than 0.1 s."

OJ 287
     L. Takalo, Nordic Optical Telescope, Santa Cruz de la Palma; and
M. Kidger, Instituto de Astrofisica de Canarias, report: "Optical
monitoring by Takalo with a CCD on the 2.5-m Nordic telescope and by
Kidger and J. A. de Diego with the CCD camera on the 1-m Jacobus
Kapteyn Telescope reveals that the BL-Lac object OJ 287 is at an
unprecedentedly faint minimum in B, with multi-color observations on
six nights in April and May revealing variations of more than one
magnitude.  At its faintest, on May 16, B = 18.06, B-V = +0.95,
indicating a very much steepened continuum.  BVRI photometry on
May 9 gave B = 17.80, B-V = +0.85, V-R = +0.32 and V-I = +0.08.  We
strongly recommend spectrophotometry of the object whilst it remains
in this faint state, during which faint underlying spectral features
are likely to be more easily observable."

     Total visual magnitude estimates: Apr. 15.49 UT, 13.3 (C. S.
Morris, 0.26-m reflector, near Mt. Wilson, CA); 29.38, 12.5
(Morris, Pine Mountain Club, CA); May 4.01, 13.0 (S. Korth,
Dusseldorf, West Germany, 0.36-m reflector); 6.99, 12.8 (Korth).

     Visual magnitude estimates: 1988 Dec. 10.75, 9.9 (S. Baroni,
Milan, Italy); 1989 Jan. 7.78, 10.0 (A. Pereira, Linda-a-Velha,
Portugal); Feb. 17.16, 9.7 (P. Schmeer, Bischmisheim, West Germany);
Mar. 7.18, 9.8 (Schmeer); 28.11, 9.9 (A. Boattini, Florence, Italy);
Apr. 9.09, 9.8 (Schmeer); May 4.04, 9.8 (Schmeer); 22.02, 10.0

1989 May 24                    (4782)              Brian G. Marsden

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