TITLE: GCN CIRCULAR NUMBER: 9247 SUBJECT: GRB 090424 : Lulin 1m telescope optical observations DATE: 09/04/25 06:06:14 GMT FROM: Yuji Urata at Nat. Central U. Y. Urata(NCU), K. Y. Huang (ASIAA) on behalf of EAFON report; "We have observed optical afterglow of GRB090424 (Cannizzo et al., GCN #9223, Yuan et al. GCN #9224; Xin et al. GCN #9225; Schady et al. #9234; Gorosabel et al. GCN #9236; Urata et al. GCN #9240, Olivares et al GCN #9245; Nissinen et al. GCN #9246) using Lulin 1m telescope (LOT) with B, V, R, I and z'-band filters. Observations started at 14:34:18 UT on 24 April. These LOT images show the afterglow clearly. Based on our preliminary photometry compared with USNO B1.0 stars, the R-band light curve between 1329 sec and 13303 sec after the burst is well fitted by a simple power law with the decay index 0.71."