TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4221 SUBJECT: GRB 051109: HET Optical Spectrum and Absorption Redshift DATE: 05/11/09 08:06:51 GMT FROM: Robert Quimby at U of Texas/ROTSE R. Quimby (U. Texas), D. Fox (PSU), P. Hoeflich (U. Texas), B. Roman, and J. C. Wheeler (U. Texas) report: We observed the optical afterglow (Rykoff et al. GCN 4211) of GRB 051109 (Tagliaferri et al. GCN 4213) with the 9.2m Hobby-Eberly Telescope (+ Marcario Low-Resolution Spectrograph) beginning November 9, 03:55:40 UT (~2.5 hrs after the burst trigger). Several absorption lines are present in the spectrum corresponding to Si II (1526.7), C IV, Cr II (2056.3, 2066.2), and Fe II (2344.2, 2382.8) among others at a redshift of z=2.346.