TITLE:   GCN CIRCULAR
NUMBER:  28733
SUBJECT: GRB 201021C: MASTER optical synchronously observation 
DATE:    20/10/21 21:46:25 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, V.Kornilov, E.Gorbovskoy, N.Tiurina, P.Balanutsa, A.Kuznetsov,K.Zhirkov, F.Balakin,
V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, A.Chasovnikov, A.Pozdnyakov,
V.Topolev, D.Cheryasov(Lomonosov Moscow State University, SAI, Physics Department),
R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico FelixAguilar OAFA),
R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias),
D. Buckley (South African Astronomical Observatory),
O.A. Gres, N.M. Budnev (Irkutsk State University, API),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
A. Gabovich, V.Yurkov, Yu. Sergienko (Blagoveschensk Educational State University)

MASTER-SAAO started GRB 201021C (Lien et al. GCN 28730) observation by
MASTER-II (2x4sq.deg.) in 2020-10-21 20:31:04UT and also detected OT at
Swift-UVOT position (Lien et al. GCN 28730) 
in 2 polarization filters.
MASTER very wide field cameras (Lipunov et al. 2010, Advances in Astronomy, vol.2010, 30L)
observed this GRB _synchronously_  .
Observation and reduction will continue.