GCN Circular 11079
A. S. Moskvitin, T. A. Fatkhullin, V. V. Sokolov, T. N. Sokolova & V. N. Komarova (SAO RAS, Niznijh Arkhyz, Russia), report: We performed the third epoch of observations of the GRB 100805A (Hoversten E. A. et al., GCN 11047) field with the Zeiss-1000 telescope of SAO RAS, Russia. The observations were carried out in the Rc band on Aug. 9.882 - 10.043 UT under good weather conditions and the seeing 1".7. At the position of OT we detected an object with R = 23.54 +/- 0.22. We assume the magnitude of the reference USNO-B1.0 star (L. P. Xin et al., GCN 11065; A. S. Moskvitin et al., GCN 11071, A. S. Moskvitin et al., GCN 11076) as R = 17.41. Also we estimate the magnitude of the source reported by V. Rumyantsev and A. Pozanenko (GCN 11077) as R = 22.31 +/- 0.08 according to their standard star with R=17.59. All errors are formal and they do not include errors of the USNO-B1.0 to Johnson-Cousins photometric system transformation. Images from all 3 epochs with the marked OT and nearby object (GCN 11077) can be found in ftp://ftp.sao.ru/pub/grb/GRB100805A/GRB100805A_Zeiss1000.jpeg This message may be cited.