TITLE: GCN GRB OBSERVATION REPORT NUMBER: 843 SUBJECT: GRB001007: Optical observations DATE: 00/10/10 19:28:27 GMT FROM: Paul Price at RSAA, ANU at CIT P.A. Price, T.S. Axelrod and B.P. Schmidt (RSAA, ANU) report: "We have observed the error box of the long, bright GRB001007 (Hurley et. al., GCN #841) with the robotic 50-inch telescope at Mount Stromlo Observatory with 3 x 300s exposures starting at Oct 10.69 (approximately 3.5 days after the burst). Our images in R_MACHO and B_MACHO cover the entire error box. We detect one object at the centre of the error box for which a counterpart is not visible on the Digital Sky Survey 2. The object is well detected in the MACHO-red frame, and faintly detected in the MACHO-blue frame. This object is located at J2000 coordinates: RA: 04:05:54.29 Dec: -21:53:45.5 Using the star at 04:05:56.44 -21:52:52.96 with assumed R=17.7 (USNO catalogue), the object has R ~ 20.3 mag. No other candidates are detected within the error box. We note that this magnitude may be near the plate limit of the DSS-2, and that an afterglow with this brightness this late after the burst is unusual. Further observations are required to verify if this is the optical transient associated with GRB001007." This message may be cited.