GCN Circular 5131
R. Starling (Amsterdam), C.C. Thoene, J.P.U. Fynbo (DARK), P. Vreeswijk (ESO) and J. Hjorth (DARK) report on behalf of a larger collaboration: We observed the optical transient of GRB 060512 (first reported by Cummings et al. GCN 5117) with the ESO FORS1 Long Slit Spectrograph under poor observing conditions, beginning at 2006-05-13 02:06:43 UT with an exposure of 2x1800s. The spectrum covers the range 3850-8750A. Preliminary analysis shows the afterglow to be blue, consistent with the magnitudes given in De Pasquale & Cummings (GCN 5130). We report a break in the continuum around 4800A and bluewards which, if identified as the onset of the Lyman-alpha forest, indicates a redshift in the range z ~ 2.7-2.9. The signal-to-noise is too low to allow identification of further lines. We thank the staff and observers at ESO Paranal.