TITLE: GCN CIRCULAR NUMBER: 7444 SUBJECT: VLT/UVES redshift of GRB 080319B DATE: 08/03/19 13:34:33 GMT FROM: Paul Vreeswijk at Dark Cosmology Centre,U.of Copenhagen P.M. Vreeswijk (DARK), A. Smette (ESO), D. Malesani, J.P.U. Fynbo, Bo Milvang-Jensen (DARK), P. Jakobsson (U. Hertfordshire), A.O. Jaunsen (U. Oslo) and C. Ledoux (ESO) report on behalf of a larger collaboration: We observed the optical afterglow of GRB 080319B (Racusin et al., GCN 7427) with the Ultraviolet and Visual Echelle Spectrograph (UVES) mounted at ESO's VLT Kueyen. Observations were performed in rapid-response mode starting on 2008 March 19 at 07:18 UT. The highest redshift system that we identify based on the MgII doublet and various other features has z=0.937, the presumed redshift of GRB 080319B. Another system is identified at z=0.530. We acknowledge excellent support from the observing staff at Paranal, in particular Swetlana Hubrig and Elena Mason.