TITLE: GCN CIRCULAR NUMBER: 25741 SUBJECT: LIGO/Virgo S190910d: MASTER previous detection of Gaia19eba/AT2019qam DATE: 19/09/13 12:18:57 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, F.Balakin, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa,A.Kuznetsov, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva, K.Pozdnyakov, A.Chasovnikov, V.Topolev, 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 Global Robotic Net (http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol.2010, 30L) started inspect of LIGO/Virgo S190910d (GCN 25695) 157 sec after trigger time at 2019-09-10 01:28:56 UT (Lipunov et al. GCN 25694) We analyzed Gaia OT candidates from compact binary merger candidate LIGO/Virgo S190910d Gaia19eba/AT2019qam ( Kostrzewa-Rutkowska et al. GCN25739 ) at RA,Dec(2000)=52.99630 -26.07598 at MASTER archieve images. There is OT with unfiltered m_OT~18.5 on 2 images at 2019-09-02 23:00:27, 22:48:02UT, it means no connection with GW S190910d