TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4163 SUBJECT: Chandra Observations of GRB 051022 DATE: 05/10/26 02:56:00 GMT FROM: Sandeep K. Patel at NSSTC-NASA/MSFC S. Patel, C. Kouveliotou (NASA/MSFC), E. Rol (University of Leicester) report on behalf of a larger team: We processed the initial 700 s (on source) of our ongoing Chandra ACIS-S observation of GRB 051022, which started on October 25, 21:14:20 UT. We detect an X-ray source consistent with the VLA source location (Cameron & Frail, GCN # 4154) with a count rate of 0.026 c/s in the entire Chandra band. The Chandra source location is centered at RA=23h56m4.1s and DEC= +19deg 36' 23.9". We estimate an error of 0.7" dominated by the uncertainty in the Chandra aspect solution. A more accurate position based on astrometry may be possible after the complete observation of 20 ks is available. We are grateful to the Chandra Data Center for the rapid data processing, in particular Drs Joy Nichols and Craig Anderson.