GRB 990123

E. Ofek and E. M. Leibowitz, Tel Aviv University, write: "From four CCD frames of the object taken at the Wise Observatory between Jan. 24.0617 and 24.1162 UT, we have determined an average R magnitude of 19.87 +/- 0.2, with calibration based on four USNO A2.0 stars. The decay parameter in the R band over that time interval is -1.9 +/- 0.1. On Jan. 24.0625, the color index of the object was B-R = -0.48 +/- 0.25."