TITLE: GCN CIRCULAR NUMBER: 29465 SUBJECT: Fermi GRB 210210B: Global MASTER-Net observations report DATE: 21/02/10 21:30:29 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-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB 210210B ( Fermi GBM team, GCN 29462) errorbox 13043 sec after notice time and 13073 sec after trigger time at 2021-02-10 20:45:00 UT, with upper limit up to 17.0 mag. The observations began at zenith distance = 67 deg. The sun altitude is -56.4 deg. The galactic latitude b = 74 deg., longitude l = 356 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1544564 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 13103 | 2021-02-10 20:45:00 | MASTER-Tavrida | (13h 33m 22.67s , +20d 18m 01.2s) | C | 60 | 12.4 | 13870 | 2021-02-10 20:57:47 | MASTER-Tavrida | (13h 40m 24.21s , +18d 19m 54.4s) | C | 60 | 13.2 | 13949 | 2021-02-10 20:59:06 | MASTER-Tavrida | (13h 31m 46.86s , +16d 19m 09.2s) | C | 60 | 12.0 | 14029 | 2021-02-10 21:00:26 | MASTER-Tavrida | (13h 33m 15.74s , +20d 18m 13.4s) | C | 60 | 17.0 | 14029 | 2021-02-10 21:00:26 | MASTER-Tavrida | (13h 39m 37.50s , +20d 16m 21.3s) | C | 60 | 13.7 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.