TITLE: GCN CIRCULAR NUMBER: 22113 SUBJECT: GRB 171010A: afterglow and SN 2017htp optical observations DATE: 17/11/09 15:51:55 GMT FROM: Alexei Pozanenko at IKI, Moscow E. Mazaeva (IKI), A. Pozanenko (IKI), V. Rumyantsev (CrAO), E. Klunko (ISTP), I. Reva (Fesenkov Astrophysical Institute), A. Kusakin (Fesenkov Astrophysical Institute), O. Burhonov (UBAI), A. Volnova (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of the Fermi-LAT GRB 171010A (Omodei et al., GCN  21985) with Zeiss-1000 telescope (TSHAO), AZT-33IK telescope (Mondy), ZTSH2.6m telescope (CrAO) and AZT-22 telescope (Maidanak). Within the enhanced Swift-XRT circle (D'Ai et al., GCN 21989) we clearly detect the optical afterglow (Thorstensen & Halpern , GCN 21987; Izzo & D. Malesani, GCN 21988; Guidorzi et al., GCN 21991; Malesani et al., GCN 22000; Harita et al., GCN 22001; Kankare et al., GCN 22002; Breeveld & Siegel, GCN 22004; Watson et al., GCN 22011; Kumar et al., GCN 22012). Still not all data received and we report some preliminary photometry of the afterglow in earlier epochs and host+OT in R-filter: Date       UT_start   t-T0      OT     Err.    Up.Lim. Telescope           (mid, days)                         (3 sigma) 2017-10-12 20:11:03 2.11360 19.06 0.04 22.4 Zeiss-1000 2017-10-13 18:34:36  3.00616    19.21  0.05    22.2 AZT-33IK 2017-10-14 18:23:31  3.99492    19.38  0.03    23.1 AZT-33IK 2017-10-15 18:23:04  4.99461    19.35  0.03    23.0 AZT-33IK 2017-10-20 00:57:51 9.26249 19.60 0.03 23.4 ZTSH2.6 2017-10-28 19:42:20 18.04966 19.50 0.06 22.8 AZT-33IK 2017-11-06 19:44:54 27.07226 20.00 0.10 21.4 AZT-22 The photometry is based on nearby USNO-B1.0 stars USNO-B.1_id R2 0795-0045061 15.10 0795-0045035 17.25 0795-0045066 16.59 A light curve of the OT+host can be found in http://grb.rssi.ru/GRB171010A/GRB171010A_light_curve_R.png As can be seen from the light curve we can support discovery of SN 2017htp (de Ugarte Postigo et al., GCN 22096; Cucchiara et al., GCN 22107). We will update the LC as more data becomes available.