TITLE: GCN CIRCULAR NUMBER: 25900 SUBJECT: LIGO/Virgo S190930t and S190930s: MASTER PSN in unknown disk galaxy DATE: 19/10/01 16:32:23 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tiurina, F.Balakin,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) is inspecting 2 LVC error-boxes: LIGO/Virgo S190930t (LVC GCN 25876, Lipunov et al. GCN 25875) and LIGO/Virgo S190930s (LVC GCN 25871, Lipunov et al. GCN25870) MASTER OT J205529.78+220725.5 discovery - PSN in unknown galaxy (=AT2019rpr) MASTER-IAC auto-detection system discovered OT source at (RA, Dec) = 20h 55m 29.78s +22d 07m 25.5s on 2019-09-30.90192 UT. The OT unfiltered magnitude is 18.3m (limit 19.3m). The OT is seen in 2 images on 2019-09-30 and on 6 images on 2019-10-01 (now). There is no minor planet at this place. We have reference image without OT on 2016-09-23.93716 UT with unfiltered magnitude limit 20.1m. Spectral observations are required. The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/205529.78220725.5.png