TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1730 SUBJECT: GRB 021204: Optical Observations at RIKEN DATE: 02/12/10 05:59:16 GMT FROM: Ken ichi Torii at RIKEN K. Torii (RIKEN), H. Yamaoka (Kyushu U.), and T. Kato (Kyoto U.) report: Starting at 15:21:26 UT on December 4th, the central 53x53 arcmin of the error region of GRB 021204 (HETE trigger 2486; GRB time 13:14:46.11 UT) was observed at RIKEN with 0.2-m f/4 reflector equipped with unfiltered CCD AP7p. Visual comparison of the first frame (30-s integration) with DSS does not show a new object brighter than ~16.5 (USNO-A2.0 red magnitude).