{
  "circularId": 45415,
  "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),\nM. Segura,  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-OAFA robotic telescope  [1]  located in Argentina (OAFA observatory of San Juan National University) was pointed to the IceCube Alert 260821A (trigger No 51776820,07h 44m 40.80s , +10d 03m 00.0s, R=0.46) errorbox  22610 sec after notice time and 22930 sec after trigger time at 2026-08-21 09:56:59 UT, with upper limit up to  16.5 mag. Observations started at twilight.  The observations began at zenith distance = 76 deg. The sun  altitude  is -15.2 deg. \n\nThe galactic latitude b = 17 deg., longitude l = 210 deg.\n\n\nReal time updated cover map and OT discovered available here: \nhttps://master.sai.msu.ru/site/master2/observ.php?id=3484669\n\nWe obtain a following upper limits.  \n\nTmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment\n_________|_____________________|_____________________|____________________________________|_____|_______|_______|________\n\n   22961 | 2026-08-21 09:56:59 |         MASTER-OAFA | (07h 45m 46.70s , +10d 07m 14.0s) |   C |    60 | 15.9 |        \n   23036 | 2026-08-21 09:58:15 |         MASTER-OAFA | (07h 45m 48.09s , +10d 08m 19.8s) |   C |    60 | 16.0 |        \n   23115 | 2026-08-21 09:59:34 |         MASTER-OAFA | (07h 45m 53.62s , +10d 07m 28.0s) |   C |    60 | 15.9 |        \n   23189 | 2026-08-21 10:00:48 |         MASTER-OAFA | (07h 45m 47.68s , +10d 06m 34.3s) |   C |    60 | 16.1 |        \n   23266 | 2026-08-21 10:02:05 |         MASTER-OAFA | (07h 45m 54.73s , +10d 06m 52.0s) |   C |    60 | 16.1 |        \n   23419 | 2026-08-21 10:04:37 |         MASTER-OAFA | (07h 45m 51.54s , +10d 07m 21.1s) |   C |    60 | 16.3 |        \n   23496 | 2026-08-21 10:05:54 |         MASTER-OAFA | (07h 45m 55.51s , +10d 08m 42.3s) |   C |    60 | 16.5 |        \nFilter C is a clear (unfiltred) band. \n\n\nThe observation and reduction will continue. \nThe message may be cited.\n\n[1] - V.M. Lipunov, V.G. Kornilov, E.S. Gorbovskoy, N.A. Tiurina & A.S.Kuznetsov, 2023,  Astronomical Robotic Networks and Operative Multichanel Astrophysics, Lomonosov MSU PRESS, 591pp.\nhttp : // www.pereplet.ru/lipunov/625.html\n",
  "editedBy": "Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of Vladimir Lipunov at Lomonosov Moscow State University, MASTER Global Robotic NET PI <lipunov2007@gmail.com>",
  "format": "text/plain",
  "submittedHow": "email",
  "editedOn": 1787519664602,
  "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>",
  "eventId": "IceCube-260821A",
  "version": 2,
  "subject": "IceCube Alert 260821A: Global MASTER-Net observations report",
  "createdOn": 1787308024335
}