TITLE: GCN CIRCULAR NUMBER: 29218 SUBJECT: Fermi trigger No 631226368: Global MASTER-Net observations report DATE: 21/01/01 21:15:28 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva, D.Kuvshinov, D. Cheryasov (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), 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-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 GRB210101.86 (trigger No 631226368,00h 41m 12.00s , -06d 54m 36.0s, R=5.18) errorbox 1084 sec after notice time and 1131 sec after trigger time at 2021-01-01 20:58:15 UT, with upper limit up to 17.5 mag. The observations began at zenith distance = 68 deg. The sun altitude is -29.6 deg. The galactic latitude b = -69 deg., longitude l = 117 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1516942 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 1222 | 2021-01-01 20:58:15 | MASTER-SAAO | (00h 33m 18.21s , -07d 00m 06.7s) | C | 180 | 17.5 | 1421 | 2021-01-01 21:01:35 | MASTER-SAAO | (00h 33m 18.46s , -07d 01m 39.8s) | C | 180 | 17.5 | 1621 | 2021-01-01 21:04:54 | MASTER-SAAO | (00h 33m 22.08s , -07d 00m 17.2s) | C | 180 | 17.4 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.