TITLE: GCN CIRCULAR NUMBER: 17446 SUBJECT: GRB 150210A: MASTER SN detection during LAT error box inspection DATE: 15/02/11 21:09:24 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs O. Gres ,K.Ivanov, S.Yazev, N.M.Budnev, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University E. Gorbovskoy, V. Lipunov, M.Pruzhinskaya, V.Kornilov, D.Kuvshinov, N.Tyurina, N.Shatskiy, P.Balanutsa, D.Zimnukhov, A.Kuznetsov, V.V.Chazov, D.Denisenko, A.Sankovich Lomonosov Moscow State University, Sternberg Astronomical Institute, Moscow State University A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University V.Krushinski, I.Zalozhnih, A. Popov Ural Federal University, Kourovka D.Buckley, S. Potter, A.Kniazev, M.Kotze South African Astronomical Observatory Hugo Levato and Carlos Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) Claudio Mallamaci, Carlos Lopez and Federico Podest Observatorio Astronomico Felix Aguilar (OAFA) MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Kislovodsk was pointed to the GRB150210A 22 sec after notice time and 1364 sec after trigger time at 2015-02-10 22:49:09 UT by FERMI GBM coordinates (ra=07 31 23 dec=+12 21 33 r=2.200000) (Burns et. al . GCN 17432). We cover a 70% part of FERMI LAT (Zhu et al. GCN 17438) error box with upper limit 17.5 MASTER II robotic telescope located in Tunka was pointed to the GRB150210A 3444 sec after the LAT notice time and 60443 sec after trigger time at 2015-02-11 15:13:47 UT. During LAT error box inspectoion MASTER-Tunka auto-detection system discovered OT source at (RA, Dec) = 07h 29m 40.10s +14d 14m 25.5s on 2015-02-11.64502 UT (Gres et al. ATel 17446). The OT unfiltered magnitude is 17.4m (the limit is 20.0m). OT is located at a distance 0.2W 2.8N from a center on unknown galaxy. It seems that this supernova was found by chance during the LAT error box inspection. OT image available here http://master.sai.msu.ru/static/OT/MASTERJ072940.10+141425.5.jpg The OT is seen in 31 images. There is no minor planet at this place. We have reference image without OT on 2012-02-18.58510 UT with unfiltered magnitude limit 19.8m. The message may be cited.