TITLE: GCN CIRCULAR NUMBER: 9285 SUBJECT: GRB 090426: YNAO-GMG observations DATE: 09/04/29 09:10:30 GMT FROM: Jirong Mao at Yunnan Obs J. Mao (YNAO & INAF-OAB), G. Cha and J. Bai (YNAO) report on behalf of the GMG group: We observed the optical counterpart of GRB 090426 (Cummings et al., GCN 9254) using one 2.4-m telescope located at Gao-Mei-GU (GMG) about 2 hours after the trigger and otained the following magnitudes: Start UT Exposure Filter Mag Err ------------------------------------- 14:07:59 20 min I 19.18 0.06 14:52:19 20 min R 20.29 0.02 15:49:27 20 min V 20.97 0.04 and calibration was processed by a nearby SDSS star in the image. The telescope is charged by Yunnan Observatory (YNAO), Chinese Academy of Sciences. This message might be cited.