TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4097 SUBJECT: GRB 051016: PROMPT Observations DATE: 05/10/16 07:30:50 GMT FROM: Melissa Nysewander at UNC,Chapel Hill M. Nysewander, D. Reichart, A. Crain, A. Foster, J. Haislip report on behalf of the UNC team of the FUN GRB Collaboration: Under the control of Skynet, PROMPT observed the localization of GRB 051016 (Boyd et al., GCN 4096) beginning 6.6 min after the burst, when the field was still at high airmass, in repeating blocks of BVRcIc (two filters simultaneously). We do not detect any new sources within or around the XRT localization. In a 12 x 80 sec integration of mean epoch 25.6 min after the burst, we measure a 3-sigma limiting magnitude of Rc = 19.1, based on 3 USNO-B1.0 stars. PROMPT is still being built and commissioned.