Swift GRB 241209D: Global MASTER-Net observations report

MASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the Swift GRB 241209D ( T. M. Parsotan et al., GCN 38489) errorbox 33929 sec after notice time and 33951 sec after trigger time at 2024-12-09 20:25:37 UT, with upper limit up to 18.8 mag. The observations began at zenith distance = 75 deg. The sun altitude is -41.5 deg. The galactic latitude b = 60 deg., longitude l = 299 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2701233 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 34041 | MASTER-Tunka | C | 180 | 15.0 | 35265 | MASTER-Tunka | C | 180 | 18.8 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.