TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4842 SUBJECT: GRB060218/SN 2006aj: optical observation DATE: 06/02/28 10:44:29 GMT FROM: Alexei Pozanenko at IKI, Moscow E. Pavlenko, Yu. Efimov, A. Shlyapnikov, V.Rumyantsev (CrAO), A.Pozanenko (IKI) on behalf of a larger collaboration report: We observed GRB 060218/SN 2006aj (Cusumano et al. GCN 4775) with CrAO Shajn 2.6m telescope on Feb. 23. A series of BVRI 30 s exposures were taken starting (UT) 19:27. Using SDSS pre-burst observations (Cool et al. GCN 4777) we estimate brightness of the optical afterglow + SN in R: Mid time, exp., R mag (UT) (s) Feb.23 19:32 8x30 s 17.40 +/- 0.01 Feb.23 19:58 8x30 s 17.41 +/- 0.01 The values is compatible with the brightening rate ~0.2 per day between Feb. 20 and Feb. 23 reported earlier (Ovaldsen et al, GCN 4818, Pavlenko et al, GCN 4838).