TITLE: GCN CIRCULAR NUMBER: 13898 SUBJECT: GRB 121024A: GMG optical observation DATE: 12/10/25 13:49:44 GMT FROM: Xiao-hong Zhao at Yunnan Obs X.-H. Zhao (YNAO), J.-R. Mao (KASI/YNAO), J.-M. Bai (YNAO) report on behalf of a larger collaboration: We observed the field of GRB 121024A (Pagani et al., GCN 13886) with 2.4m Gao-Mei-Gu (GMG) telescope. Observations started at 16:30:00 UT on 2012-10-24 (i.e., 13.6 hrs after the burst) and 2x900s R-band images were obtained. The optical afterglow of this burst was clearly detected. The results are as follows: mid time from trigger (hr) Mag. Err. Exposure time (second) 13.69 20.88 0.1 900 13.81 20.81 0.1 900 We thank the GMG staff, especially Fang Wang, De-Qing Wang and Jian-Duo He for performing these observations.