Hanjie Tan (Institute of Astronomy, National Central University), Mi Zhang, Guoyou Sun, Jingyuan Zhao (Xingming Observatory), Quanzhi Ye , Xing Gao (Xingming Observatory), report ~1.6 mag outburst in a variable star candidate (G=16.10+-0.12). The source appears to correspond to object Gaia DR2 1980780883322175360 (G=17.73) in the Gaia DR2. Discovery was made on several 120-s survey images (limiting mag about 18.0) taken by Xing Gao at Xingming Observatory #3 (N88) around Sep. 20.76184, 2021 UT using a unfiltered CCD (0.3-m f/3.6 reflector). Images can be found at: http://xjltp.china-vo.org/xm71ht.html
XM71HT C2021 09 20.76184 21 46 14.74 +51 07 28.9 16.10 G N88