TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2789 SUBJECT: GRB 041006: Colour measurement DATE: 04/10/08 21:26:52 GMT FROM: Paul Price at IfA,UH G. Da Costa (RSAA, ANU) and N. Noel (IAC) report: We have reduced our observations of the afterglow of GRB 041006 (GCN #2765). From observations of several photometric standards taken the same night, we find that the star at coordinates 00:54:37.96, +01:13:00.7 J2000 (i.e. south west of the offset star in the finder from GCN #2766) has B = 18.28 mag and V = 17.35 mag. From these, we estimate that the afterglow had a B-V colour of approximately 0.28 +/- 0.03 mag around 2004 Oct 6.58 UT.