GRB 241128A: 1.5m OSN optical afterglow detection

Following the detection of GRB 241128A by Swift (Brivio et al. GCN 38367), we triggered the 1.5m OSN telescope in Granada (Spain) starting on Nov 28, 18:19 UT (~2.1 hrs post burst) in R & I-bands. An uncatalogued object is detected within the XRT error circle (Page et al. GCNC 38368) with R=19.3+-0.1 mag, at coordinates RA(J2000) = 18:14:53.55, DEC(J2000) = +33:26:20.32, which we proposed as the GRB 241128A optical afterglow. Spectroscopic observations are encouraged. We thank the staff at OSN for their excellent support.