{
  "body": "V.Lipunov, E.Gorbovskoy, A.Kuznetsov, K.Zhirkov, I.Panchenko, N.Tiurina, P.Balanutsa, V.Topolev, D.Vlasenko, \nG.Antipov,  A.Sankovich, Yu.Tselik, Ya.Kechin, V.Senik, A.Chasovnikov, K.Labsina, I. Gorbunov (Lomonosov MSU),\nO.Gress, N.Budnev (ISU),\nC.Francile,  F. Podesta, R.Podesta, E. Gonzalez  (Observatorio Astronomico Felix Aguilar (OAFA),\nA. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),\nA.Sosnovskij (CrAO),\nA. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity),\nD.Buckley (SAAO),\nR.Rebolo (The Instituto de Astrofisica de Canarias),\nL.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,\nA.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory) \n\nMASTER-SAAO robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB 250918A ( Fermi GBM team, GCN 41865) errorbox  1 days 18846 sec after notice time and 1 days 18882 sec after trigger time at 2025-09-19 17:47:00 UT, with upper limit up to  15.6 mag. Observations started at twilight.  The observations began at zenith distance = 60 deg. The sun  altitude  is -16.5 deg. \n\nThe galactic latitude b = 38 deg., longitude l = 340 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=2994371\n\nWe obtain a following upper limits.  \n\nTmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n  105313 | 2025-09-19 17:47:00 |         MASTER-SAAO | (14h 44m 17.11s , -15d 37m 24.9s) |   C |    60 | 15.6 |        \n  105313 | 2025-09-19 17:47:00 |         MASTER-SAAO | (14h 46m 06.96s , -15d 52m 16.6s) |   C |    60 | 14.9 |        \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n",
  "subject": "Fermi GRB 250918A: Global MASTER-Net observations report",
  "circularId": 41889,
  "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>",
  "bibcode": "2025GCN.41889....1L",
  "submittedHow": "email",
  "createdOn": 1758306647368,
  "eventId": "GRB 250918A"
}