TITLE: GCN CIRCULAR NUMBER: 10030 SUBJECT: GRB 091010: optical obsevation DATE: 09/10/17 02:11:22 GMT FROM: Alexei Pozanenko at IKI, Moscow V. Rumyantsev (CrAO), E. Klunko (ISTP) and A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of SuperAGILE GRB 091010 (Donnarumma et al. GCN 10004) with Shajn telescope of CrAO on Oct. 12 between (UT) 16:55:18 - 18:09:40. In the XRT error circle (Margutti et al. GCN 10006) we detect a single object at coordinates (J2000) RA: 19 54 39.80 Dec: -22 31 04.71. The coordinates of the object coincide with OT candidate reported by Rossi et al. (GCN 1008). The photometry against nearby USNO-B1.0 stars (0674-0991940 RA:19 54 39.26 Dec: -22 31 29.7 R=18.18, 0674-0991922 RA:19 54 38.07 Dec: -22 31 12.4 R=17.27) is following: T0+ Filter, Exposure, mag., err. (d) (s) 2.62 R 71x60 22.40 +/- 0.17 Our photometry confirm the absence of variability of the OT candidate (Rossi et al.GCN 1008, Guidorzi et al.GCN 10027). However the object looks like extended in E-W direction, and can be a candidate in a host galaxy of GRB 091010. The combined image can be found in http://grb.rssi.ru/GRB091010/GRB091010_091012_R_ZTSh.gif