TITLE: GCN CIRCULAR NUMBER: 45123 SUBJECT: Fermi LAT GRB 260708A: MASTER OT J150237.02-435307.7 optical counterpart detection DATE: 26/07/09 10:23:14 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru> M.Shilova, K.Zhirkov, V.Lipunov, A.Kuznetsov, P.Balanutsa, G.Antipov, I.Panchenko, N.Tiurina, Ya.Kechin, E.Gorbovskoy, V.Senik, A.Chasovnikov, V.Topolev,D.Vlasenko,A.Sankovich, I.Gorbunov, V.Fedorova, A.Telnova (Lomonosov MSU), F.Podesta, M.J. Segura, C.Francile, R.Podesta, E. Gonzalez (OAFA, SJNU), D.Buckley (SAAO), A.Sosnovskij (CrAO RAS), N.Budnev, O.Gress (ISU), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A. Gabovich (Blagoveschensk Educational StateUniversity) R.Rebolo (The Instituto de Astrofisica de Canarias), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez,J.Martinez,A.R.Corella, J.Tanori, L. Villalobos, L.H.Rodriguez (INAOE, Guillermo Haro AstrophysicsObservatory) MASTER-OAFA and MASTER-SAAO robotic telescopes of MASTER Global Robotic Net [1-4] was pointed to the Fermi LAT GRB 260708A (Holzmann Airasca et al. GCN 45117, trigger 2026-07-08 10:11:16.89 UT, RA, Dec = 225.61, -44.07 +-0.27 (J2000)) at 2026-07-08 22:40:00 UT (Lipunov et al. 45119). There is optical counterpart of GRB 260708A MASTER OT J150237.02-435307.7 https://www.wis-tns.org/object/2026stf discovered by MASTER auto-detection system [1-4] at 2026-07-08 22:42:34.272UT with unfiltere m~17.6m. The typical light curve points to GRB source. spectral observations is required. [1] Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L [2] Lipunov et al. 2022, Universe, Vol. 8(5), id.271 [3] Lipunov et a. 2019, ARep, vol.63, 293 [4] Lipunov et al. 2023, Astronomical Robotic Networks and Operative Multichanel Astrophysics,Lomonosov MSU PRESS, 591pp. http://www.pereplet.ru/lipunov/625.html#625 View this GCN Circular online at https://gcn.nasa.gov/circulars/45123. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...