Аннотация:MASTER-Kislovodsk auto-detection system discovered OT source at (RA, Dec) = 05h 10m 02.32s +18d 00m 41.5s on 2012-09-25.07681 UT. The OT unfiltered magnitude is 16.2m (limit 19.0m). The OT is identical to QSO B0507+179 = PKS 0507+179 = NVSS J051002+180041 = USNO-B1.0 1080-0080773 (catalog magnitude R=19.09). We have 14 past positive observations of this object in MASTER-Kislovodsk database, 9 in MASTER-Tunka and 3 in MASTER-Amur with the range of variability from 18.7 to 16.6 mag (unfiltered with the Red zero point).