GCN Circular 12385
D. Xu (WIS), L.P. Xin, J.Y. Wei (NAOC) report on behalf of a larger collaboration: We performed astrometry to the TNT image (Xin et al., GCN 12377), calibrated with the SDSS field of GRB 110921A (Baumgartner et al., GCN 12373). The optical afterglow is localised at RA (J2000): 19h 36m 23.478s Dec (J2000): +36d 19' 43.38" with an uncertainty of 1.0 arcsec, in the northwestern part of the enhanced XRT error circle (Goad et al., GCN 12379). The SDSS field reveals a source at coordinates RA (J2000): 19h 36m 23.382s Dec (J2000): +36d 19' 42.03" with an uncertainty of 1.0 arcsec and at the southwestern edge of the XRT error circle, which is too faint to be present for the TNT image. NIR follow-up observation is encouraged.