BELGIAN ASTRONOMICAL SOCIETY V.V.S. - Working Group Variable Stars Cataclysmic Variables Circular No.11 1994, August 17 Ed.: P. Van Cauteren, de Borrekenslaan 54, 2630 Aartselaar, BELGIUM 73064.1123@compuserve.COM TEL. 32-3-8774098 T. Vanmunster, Walhostraat 1A, 3401 Landen, BELGIUM Internet: tvm@lms.be TEL. 32-11-831504 =================================================================== UZ Boo [UGWZ, 11.5v - 20.4V] ============================ Dave York, Abiquiu, NM has informed us about his detection of an outburst of this very important WZ Sge type dwarf nova. Available observations : 1994 Aug 15.891, [13.3 (T. Vanmunster, 0.35-m refl, moon, seq AAVSO); Aug 16.458, [15.1 (M. Iida, Nagano, Japan, 0.16-m refl. + ST-6 CCD unfiltered); Aug 17.167, 13.9 (D. York, 0.45-m refl, seq AAVSO); Aug 17.224, 13.9 (D. York); Previous outbursts of this recurrent object were seen in 1929, 1937, 1938, 1940 and 1978 (when it reached mag 11.5). Observers are strongly encouraged to send us their observations of the present outburst, since professionals have shown considerable interest in this star. Only limited photometric and spectroscopic measurements of the UZ Boo system are available : in a 1988 paper [1], S. Howell and P. Szkody indicate that photometry of UZ Boo did not show evidence of a near three hours orbital period, as was stated in an earlier paper [2]. [1] Howell, B., and Szkody, P, 1988, PASP, 100, 224-232 [2] Szkody, P., 1987, Ap.J.Suppl., 63, 685-699 V493 Lyr = S10930 Lyr [UG] ========================== Tonny Vanmunster, Landen, Belgium has detected an outburst of this dwarf nova, as indicated by the observations below : 1994 Aug 14.938, [15.1 (G. Poyner, UK, 0.40-m refl, seq TA); Aug 15.507, [16.1 (M. Iida, Japan, 0.16-m refl + ST-6 CCD unfiltered); Aug 15.886, [14.1 (T. Vanmunster, 0.35-m refl, seq TA); Aug 16.997, 14.9 (T. Vanmunster); Aug 17.049, 14.8 (T. Vanmunster); This star was last seen in outburst on Oct 24, 1993 (John Bortle, USA and Paul Van Cauteren, Belgium), which were first ever visual observations. Confirmative observations are encouraged. V344 Lyr [UGSU, 14.5p - <20p] ============================= This dwarf nova was in outburst early this month, only a few weeks after its superoutburst of July 1994 [CVC No.9]. The present outburst was detected by Tonny Vanmunster and subsequently confirmed by Eric Broens, Balen, Belgium and by Gary Poyner, Birmingham, UK, as indicated by the observations below. 1994 Aug 1.906 UT, 14.9 (T. Vanmunster, 0.35-m refl, seq TA); Aug 1.929 UT, [14.8 (G. Poyner, 0.40-m refl, seq TA); Aug 1.958 UT, 14.9 (E. Broens, 0.35-m refl, seq TA); Aug 2.028 UT, 15.0 (G. Poyner); Aug 2.101 UT, 15.0 (G. Poyner); Aug 2.894 UT, 15.0 (T. Vanmunster); Aug 2.956 UT, 14.9 (E. Broens); Aug 3.901 UT, [14.8 (T. Vanmunster); Tonny Vanmunster