TITLE: GCN CIRCULAR NUMBER: 30476 SUBJECT: GRB 210722A: Nanshan/NEXT optical afterglow observations DATE: 21/07/22 21:58:22 GMT FROM: Dong Xu at NAOC/CAS Z.P. Zhu (NAOC, HUST), S.Y. Fu, D. Xu, X. Liu (NAOC), X. Gao (Urumqi No.1 Senior High School), J.Z. Liu (XAO) report: We observed the field of GRB 210722A (D'Avanzo et al., GCN 30475) using the NEXT-0.6m telescope located at Nanshan, Xinjiang, China. We obtained a series of 40 s, 60 s, 90 s frames in the Sloan r-band, starting at 20:56:45 UT on 2021-07-22, i.e., 123 s after the BAT trigger, among which part of the frames are useless due to the cloudy weather. An uncatalogued optical transient is detected at the Swift/UVOT position (D'Avanzo et al., GCN 30475) with varying brightness, and thus confirms it as the optical afterglow of the burst. Preliminary analysis of the beginning photometry is as follows: Tmid-T0(sec) Mag MagErr 143 14.33 0.01 361 13.94 0.01 452 14.01 0.01 All magnitudes are calibrated with the nearby PS1 field.