TITLE: GCN CIRCULAR NUMBER: 20133 SUBJECT: GRB 161105A: MASTER-IAC early optical observations DATE: 16/11/05 10:56:14 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E.Gorbovskoy, N.Tyurina, V.Kornilov, O.Gress, P.Balanutsa, A.Kuznetsov, D.Kuvshinov Lomonosov Moscow State University, Sternberg Astronomical Institute R. Rebolo, M. Serra Ricart, N. Lodieu, G. Israelian The Instituto de Astrofisica de Canarias R.Podesta, C.Lopez, F.Podesta Observatorio Astronomico Felix Aguilar (OAFA), San Juan Univerdity, H. Levato, C. Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) D.Buckley, S. Potter, South African Astronomical Observatory O.Gres, K.Ivanov, J.Rabinovich, N.M.Budnev, Irkutsk State University A. Tlatov, V.Senik, D. Dormidontov, A.Parkhomenko Kislovodsk Solar Station of the Pulkovo Observatory V.Yurkov, Yu.Sergienko, A.Gabovich Blagoveschensk Educational State University, Blagoveschensk MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in IAC was pointed to the GRB161105A 27 sec after notice time and 42 sec after trigger time at 2016-11-05 04:53:44 UT. On our first (10s exposure) set we haven`t found optical transient within SWIFT error-box (ra=120.163 dec=-44.7794 r=0.05) (Page et al., GCN 20131). The 5-sigma upper limit has been about 16.4 mag (polaroid, unfiltered). The observations made on zenit distance = 75 degrees, galaxy latitude b = -7 degree. The moon (25 % bright part) below the horizon (The altitude of the Moon is -80 degree ). The sun altitude is -32.4 degree. The object can be observed till sunrise at 2016-11-05 07:20:31 Maximal coadded limit ~19.5 m. No OT found. The message may be cited.