Аннотация:MASTER OT J212444.87+321738.3 - new very bright variable MASTER-Amur auto-detection system discovered OT source at (RA, Dec) = 21h 24m 44.87s +32d 17m 38.3s on 2013-03-13.84134 UT. The OT unfiltered magnitude is 10.7m (limit 16.9m). The OT is seen in 6 images. There is no minor planet at this place. We have reference image with OT at 13.5m on 2012-10-21.52326 UT (magnitude limit 18.5m).