V589 Her possible superoutburst YYYYMMDD(UT) mag observer 20230225.7745 <154c (Yutaka Maeda) 20230226.7276 <160c (Yutaka Maeda) 20230227.7272 <156c (Yutaka Maeda) 20230302.7736 148:c (Yutaka Maeda) 20230302.8352 151C (Masayuki Moriyama)