TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1572 SUBJECT: GRB021004: Upper limits from recent and historical observations DATE: 02/10/05 00:12:36 GMT FROM: Brian Lee at LBL W. M. Wood-Vasey, G. Aldering, and B. C. Lee, Lawrence Berkeley National Laboratory, using images obtained by E. F. Helin, S. Pravdo, M. Hicks, and K. Lawrence (Near-Earth Asteroid Tracking project, Jet Propulsion Laboratory), report upper limits for pre-discovery observations at the location of the object identified by Fox et al. (GCN 1564) as the optical counterpart to GRB 20021004 from unfiltered observations with the Oschin 48" telescope at Palomar Observatory (the same instrument as used by Fox et al.). A co-addition of historical images from 13 October 2001, 26 October 2001, 5 November 2001, 3 September 2002, 3 October 2002 (all dates UT) from the same instrument show no source visible at this location to a limiting unfiltered magnitude of 22.3 (calibrated to USNO R-band stars on the image frame) at a S/N of 3. A coaddition of images from 3 October 2002 UT shows no source visible at this location to a limiting unfiltered magnitude of 21.4 (calibrated to USNO R-band stars on the image frame) at a S/N of 3. The specific UT times for the 3 October 2002 UT observations are: 07:24:18 07:54:50 08:25:19 The historical co-additions of the all images mentioned above is available at: http://supernova.lbl.gov/~wwoodvas/GRB/