TITLE: GCN CIRCULAR NUMBER: 7461 SUBJECT: GRB080319B: Prompt PROMPT Detections DATE: 08/03/19 20:21:30 GMT FROM: Mark Schubel at UNC/PROMPT M. Schubel, D. Reichart, M. Nysewander, A. LaCluyze, K. Ivarsen, J. A. Crain, A. Foster, T. Brennan, J. Haislip, J. Styblova, and A. Trotter report: Skynet observed the localization of GRB 080319B (Racusin et al., GCN 7427) with three of the 16" PROMPT telescopes at CTIO beginning 32 seconds after the trigger (15 seconds after notification) in UVRI. We detect the afterglow (Racusin et al., GCN 7428) in all filters. At 92 seconds after the burst we measure V ~ 8.6 mag (calibrated to 3 NOMAD stars), and at 147 seconds we measure I ~ 8.9 mag (calibrated to 6 USNO B1 stars).