TITLE: GCN CIRCULAR NUMBER: 25587 SUBJECT: Fermi trigger No 588931056 Global MASTER-Net observations report DATE: 19/08/31 08:31:17 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva, D.Kuvshinov (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), H.Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE), R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), O.A. Gres, N.M. Budnev, O.Ershova (Irkutsk State University, API), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), V. Yurkov, A. Gabovich, Yu. Sergienko (Blagoveschensk Educational State University) MASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB190831.33 (trigger No 588931056,04h 34m 02.400s , +19d 14m 24.00s, R=3.37) errorbox 154 sec after notice time and 166 sec after trigger time at 2019-08-31 08:00:17 UT, with upper limit up to 18.1 mag. The observations began at zenit distance = 62 deg. The sun altitude is -37.5 deg. The galactic latitude b = -60 deg., longitude l = 98 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1121102 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 182 | 2019-08-31 08:00:17 | MASTER-OAFA | (04h 32m 42.093s , +19d 12m 22.97s) | C | 30 | 18.1 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.