Hanjie Tan, Guoyou Sun, Mi Zhang, Xing Gao (Xingming Observatory), report ~4.1 mag outburst in a known QSO ( 16.55 r ) which is 20.64 rmag in Pan-STARRS DR1 catalogue. The transient was discovered on several 120-s survey images ( limiting mag about 18.0 ) taken by Xing Gao at Xingming Observatory #3 ( N88 ) around Jan. 25.89179, 2021 UT using a unfiltered CCD ( 0.3-m f/3.6 reflector ). Images can be found at: http://xjltp.china-vo.org/xm42ht.html
XM42HT C2021 01 25.89179 13 08 23.73 +35 46 37.0 16.55 r N88
*Known QSO LQAC_197+035_002