THE AMERICAN ASSOCIATION OF VARIABLE STAR OBSERVERS 25 Birch Street, Cambridge, MA 02138 USA BITNET: aavso@cfa SPAN: cfa::aavso INTERNET: aavso@cfa.harvard.edu Tel. 617-354-0484 FAX 617-354-0665 AAVSO ALERT NOTICE 186 (June 1, 1994) BRIGHT OUTBURST OF 0203+56A UV PERSEI The dwarf nova-type cataclysmic variable UV Per is having a bright outburst (possibly superoutburst), as indicated by the observations below: May 17.96 UT, < 13.6 T. Vanmunster, Landen, Belgium); 22.08, < 13.0 P. Schmeer, Bischmisheim, Germany); 29.91, 11.9 (Vanmunster); 29.96, 11.8 (Vanmunster) ;; 29.99, 11.9 (Vanmunster); 30.92, 12.1 (Vanmunster); 31.00, 11.5 (G. Poyner, Birmingham, England); 31.02, 11.9 (Vanmunster); 31.05, 11.8 (Schmeer); 31.99, 11.7 (Poyner); Jun 1.04, 11.6 (Schmeer);1.48, 10.5 (R. Royer, Lakewood, CA). The two most recent outbursts of UV Per were in April 1993, when it reached 12th magnitude at maximum and was brighter than 13th magnitude for 3 days, and in December 1991, a bright and long outburst when it reached llth magnitude and stayed brighter than 13th magnitude for 10 days. If this is indeed a superoutburst (a long and a bright outburst), and if at all possible, both visual observers and those with CCDs are strongly recommended to look for its superhumps (oscillations of several tenths of a magnitude and a period of 1 hour and 35.9 minutes). Observations made every 5 to 10 minutes and the exact time (to 4 decimals of the JD) are needed. Accompanying is an AAVSO 'f' scale chart of UV Per. Notice that the sequence for this star was revised considerably in 1981, and that the latest issue of this chart is 1986. Please make sure that you have replaced any pre-1981 UV Per chart in your files with this one. When you report your observations to AAVSO Headquarters, please indicate which chart (including date of issue) and which comparison stars you are using. 1824-17 NOVA SAGITTARII 1994 NUMBER 2 This nova is brightening, as indicated by the following observations: May 24.30 UT, 11.8 (C. Scovil, Stamford, CT); 26.44, 11.1 (R. Royer, Lakewood, CA); 27.91, 10.8 (D. Overbeek, Edenvale, South Africa); 28.36, 11.0 (Royer); 29.31, 10.8 (Royer); 30.01, 10.7 (Overbeek); 30.23, 11.1 (R. Stewart, Rochelle Park, NJ); 30.27, 10.2 (Royer); 30.30, 10.7 (Scovil); 31.01, 10.4 (T. Vanmunster, Landen, Belgium); 31.22, 10.8 (J. McKenna, Upper Montclair, NJ); June 1.09, 10.3 (P. Schmeer, Bischmisheim, Germany); 1.44,10.4 (E. Halbach, Estes Park, CO); 1.48, 10.2 (Royer). Please monitor this nova closely, using the chart distributed with AAVSO Alert Notice 185, and report your observations to Headquarters. 2337+56 NOVA CASSIOPEIAE 1993 This interesting nova reached minimum in March at about 15th magnitude, started to recover in mid-April, and continues to brighten, as indicated by the observations below: May 15.04 UT, 12.8 (K. Sarneczky, Raktanya, Hungary); 15.94, 13.3 (T. Vanmunster, Landen, Belgium); 15.97, 13.3 (A. Diepvens, Balen, Belgium); 18.00, 13.3 (Vanmunster); 13.0 (R. Royer, Lakewood, CA); 20.06, 13.4 (Vanmunster); 20.07, 13.4 (Vanmunster); 28.26, 13.1 (R. Stewart, Rochelle Park, NJ); 28.40, 12.8 (Royer); 29.94, 12.3 (Vanmunster); 30.94, 12.1 (Vanmunster); 31.07, 12.2 (G. Poyner, Birmingham, England); 31.07, 12.3 (P. Schmeer, Bischmisheim, Germany); 31.34, 12.5 (P. Robbins, Kansas City, KS); Jun 1.04, 12.2 (Poyner); 1.06, 12.2 (Schmeer); 1.50, 12.7 (Royer). It is predicted that N Cas 93 will reach a second maximum which will be much fainter than the first maximum, and then will slowly decline, as was the case with DQ Her. Please continue to observe this nova closely, and report your observations to AAVSO Headquarters. SUPEROUTBURST OF 0409-71 VW HYDRI VW Hyi is having a superoutburst, as indicated by the following observations: May 29.71, 12.3 (D. Overbeek, Edenvale, South Africa); 30.07, 11.4 (Overbeek); 30.68, 8.4 (L. Monard, Pretoria, South Africa); 30.69, 8.9 (Overbeek); 31.10, 8.9 (Overbeek); 31.16, 8.6 J. Smit, Waverly, South Africa); 31.70, 8.4 (J. Hers, Sedgefield, South Africa); Jun 1.70, 8.2 (Hers). Astronomers planning to observe this star with EUVE satellite have been alerted to this outburst for possible scheduling of the satellite to make pointed observations. Please monitor this star closely and report your observations to AAVSO Headquarters throughout its outburst so that we may inform the astronomers. REMINDER ON 2138+43 SS CYGNI Please keep a close eye on SS Cyg and alert us when it starts to brighten, i.e., brighter than 11.5, as several astronomers are interested in monitoring its outburst with the IUE and EUVE satellites (see AAVSO Alert Notice 184). The answering machine at AAVSO Headquarters is on nights and weekends for your convenience. Thank you very much for all your efforts and your vital astronomical contributions. Clear skies and good observing! Janet A. Mattei Director