GCN Circular 332
G. Marconi and G.L. Israel (Observ. of Rome, Italy), D. Lazzati, S. Covino and G. Ghisellini (Observ. of Brera, Milan, Italy) report: A 40 min exposure taken at ESO-NTT-SUSI2 1999, May 17.1066, with a seeing of 1.2" shows the OT of GRB990510 at the magnitude R=23.4+-0.1 (assuming R=16.5 for the USNO star at RA = 13:38:00.82, DEC=-80:29:11.7). A 50 min exposure taken on May 18.1306 (1" seeing) shows the OT at R=23.7+\-0.1. No obvious candidate host galaxy can be seen. The NTT images are posted at: http://www.merate.mi.astro.it/~gabriele/990510/ This message is citeable.