TITLE: GCN CIRCULAR NUMBER: 30439 SUBJECT: Fermi trigger No 647641569: Global MASTER-Net observations report DATE: 21/07/10 20:45:21 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-Kislovodsk robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB210710.85 (trigger No 647641569,19h 03m 55.20s , +26d 48m 36.0s, R=2.7) errorbox 18 sec after notice time and 48 sec after trigger time at 2021-07-10 20:26:52 UT, with upper limit up to 17.0 mag. The observations began at zenith distance = 18 deg. The sun altitude is -23.8 deg. MASTER-SAAO robotic telescope located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB210710.85 errorbox 26 sec after notice time and 56 sec after trigger time at 2021-07-10 20:27:01 UT, with upper limit up to 17.6 mag. The observations began at zenith distance = 65 deg. The sun altitude is -58.1 deg. The galactic latitude b = 9 deg., longitude l = 59 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1657284 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 53 | 2021-07-10 20:26:52 | MASTER-Kislovodsk | (19h 07m 43.21s , +26d 34m 39.7s) | C | 10 | 16.2 | 62 | 2021-07-10 20:27:01 | MASTER-SAAO | (19h 04m 25.67s , +26d 38m 18.6s) | C | 10 | 17.6 | 83 | 2021-07-10 20:27:22 | MASTER-Kislovodsk | (19h 07m 49.35s , +26d 33m 35.3s) | C | 10 | 15.5 | 118 | 2021-07-10 20:27:52 | MASTER-Kislovodsk | (19h 07m 43.16s , +26d 32m 34.3s) | C | 20 | 16.9 | 164 | 2021-07-10 20:28:32 | MASTER-Kislovodsk | (19h 07m 48.20s , +26d 32m 40.8s) | C | 30 | 17.0 | 218 | 2021-07-10 20:29:22 | MASTER-Kislovodsk | (19h 07m 45.88s , +26d 34m 31.6s) | C | 40 | 16.2 | 284 | 2021-07-10 20:30:23 | MASTER-Kislovodsk | (19h 07m 45.64s , +26d 32m 50.1s) | C | 50 | 15.8 | 359 | 2021-07-10 20:31:33 | MASTER-Kislovodsk | (19h 07m 48.07s , +26d 34m 08.1s) | C | 60 | 16.7 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.