TITLE:   GCN CIRCULAR
NUMBER:  29225
SUBJECT: MAXI GRB210102.38: Global MASTER-Net observations report 
DATE:    21/01/02 15:51:10 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

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 MAXI GRB210102.38 (trigger No 216347865,23h 33m 17.52s , -21d 05m 09.6s, R=1) errorbox  20657 sec after notice time and 22218 sec after trigger time at 2021-01-02 15:14:28 UT, with upper limit up to  18.6 mag. Observations started at twilight.  The observations began at zenith distance = 66 deg. The sun  altitude  is -10.2 deg. 

The galactic latitude b = -72 deg., longitude l = 49 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1517221

We obtain a following upper limits.  

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

   22308 | 2021-01-02 15:14:28 |      MASTER-Tavrida | (23h 38m 28.04s , -21d 16m 44.6s) |   C |   180 | 16.5 |        
   22447 | 2021-01-02 15:17:47 |      MASTER-Tavrida | (23h 40m 11.97s , -22d 12m 44.8s) |   C |    60 | 16.8 |        
   22447 | 2021-01-02 15:17:47 |      MASTER-Tavrida | (23h 33m 48.28s , -22d 08m 48.5s) |   C |    60 | 17.1 |        
   23188 | 2021-01-02 15:29:07 |      MASTER-Tavrida | (23h 38m 29.61s , -21d 16m 08.3s) |   C |   180 | 18.0 |        
   23188 | 2021-01-02 15:29:07 |      MASTER-Tavrida | (23h 32m 05.67s , -21d 12m 28.7s) |   C |   180 | 17.8 |        
   23327 | 2021-01-02 15:32:27 |      MASTER-Tavrida | (23h 38m 17.21s , -20d 11m 56.3s) |   C |    60 | 17.9 |        
   23327 | 2021-01-02 15:32:27 |      MASTER-Tavrida | (23h 31m 55.64s , -20d 08m 18.0s) |   C |    60 | 18.3 |        
   23407 | 2021-01-02 15:33:46 |      MASTER-Tavrida | (23h 40m 12.49s , -22d 11m 02.2s) |   C |    60 | 18.0 |        
   23407 | 2021-01-02 15:33:46 |      MASTER-Tavrida | (23h 33m 45.80s , -22d 07m 25.1s) |   C |    60 | 18.4 |        
   23546 | 2021-01-02 15:35:05 |      MASTER-Tavrida | (23h 38m 28.70s , -21d 17m 17.2s) |   C |   180 | 18.6 |        
   23546 | 2021-01-02 15:35:05 |      MASTER-Tavrida | (23h 32m 04.24s , -21d 13m 40.4s) |   C |   180 | 18.6 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.