RZ Sge superoutburst? The SU UMa-type dwarf nova RZ Sge is undergoing a bright outburst (possible superoutburst). The latest superoutburst of RZ Sge occurred in 1998 December. YYMMDD(UT) mag observer 990716.958 <143 (E. Muyllaert) 990717.049 <155 (G. Poyner) 990717.965 <143 (E. Muyllaert) 990717.999 <163 (C. P. Jones) 990718.072 <153 (G. Poyner) 990718.944 131 (J. Ripero) 990718.972 132 (E. Muyllaert) 990719.966 130 (M. Reszelski) 990720.958 126 (C. P. Jones)