TITLE:   GCN CIRCULAR
NUMBER:  4118
SUBJECT: GRB051021.6: MASTER optical observation
DATE:    05/10/21 16:14:23 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <gcncirc@observ.inetcomm.ru>

V. Lipunov, V.Kornilov, D.Kuvshinov, N.Tyurina, A.Belinski, E.Gorbovskoy,
A.Krylov, G.Borisov, A.Sankovich, V.Vladimirov

Sternberg Astronomical Institute, Moscow Union 'Optic'
MASTER  robotic system (http://observ.pereplet.ru) responded to
  GRB051021.6  at 2002-10-21 15:39:37 under the bad weather conditions 
after sunset.

An automated response took the first image at 01h 28min  after the GRB 
time.
The unfiltered image is calibrateds relative to USNO A2.0 (0.8 R + 0.2 B).
The robot not find OT-candidate in error box.
Our upper limit is about  14.0 m.
The reduction is continuing.
The JPG-image will be   available at
http://observ.pereplet.ru/images/GRB051021.6/1.jpg  .
This work is supported by RFFI  04-02-16411 grant.
This message can be cited.