Hanjie Tan and Xing Gao, report ~3.1 mag outburst in a known variable star ( 15.78 r ) which is 18.91 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 Sep. 02.69997 UT using a unfiltered CCD ( 0.3-m f/3.6 reflector ). Images can be found at: http://xjltp.china-vo.org/xm15ht.html
XM15HT C2020 12 02.69997 22 52 13.71 +60 50 17.0 15.78 r N88
*Known VS ZTF J225213.87+605017.6
