V660 Her superoutburst YYYYMMDD(UT) mag observer 20190503.048 <161 (Pavol A. Dubovsky) 20190503.703 <152 (Hiroyuki Maehara) 20190504.6728 152:cG (Yutaka Maeda) 20190505.6433 147cG (Yutaka Maeda) 20190505.756 150 (Hiroyuki Maehara)