TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3922 SUBJECT: GRB 050904: Afterglow Astrometry DATE: 05/09/05 17:25:07 GMT FROM: Daniel E. Reichart at U.North Carolina M. Nysewander, D. Reichart, J. Haislip report on behalf of the UNC GRB team of the FUN GRB Collaboration: Using a single 348 sec coadd from last night's SOAR data (Haislip et al., GCN 3919) and 7 USNO stars, we measure the coordinates of the afterglow to be: RA: 00:54:50.794 DEC: +14:05:09.42 with uncertainties of 1.6" in RA and 2.3" in DEC. This is consistent with the astrometry of D'Avanzo et al. (GCN 3921) and the refined coordinates of the X-ray afterglow (Mineo et al.; GCN 3920). DR apologizes for the crudeness of our initial astrometry.