HS Vir indeed superoutburst YYYYMMDD(UT) mag observer 20170416.615 <148 (Hiroyuki Maehara) 20170422.633 135 (Hiroyuki Maehara) 20170422.731 143C (Masayuki Moriyama) 20170423.419 140 (Rod Stubbings) 20170423.592 133 (Yoshiyasu Sato) 20170424.576 134 (Yoshiyasu Sato)