TITLE: GCN CIRCULAR NUMBER: 7439 SUBJECT: GRB 080319b prompt optical observation by Pi-of-the-Sky DATE: 08/03/19 11:55:07 GMT FROM: Grzegorz Wrochna at Soltan Inst.for Nuclear Studies M.Cwiok, W.Dominik, G.Kasprowicz, A.Majcher, A.Majczyna, K.Malek, L.Mankiewicz, M.Molak, K.Nawrocki, L.W.Piotrowski, D.Rybka, M.Sokolowski, J.Uzycki, G.Wrochna, A.F.Zarnecki on behalf of "Pi of the Sky" collaboration http://grb.fuw.edu.pl "Pi of the Sky" apparatus located at Las Campanas Observatory imaged the region of GRB 080319b (Swift triger 306757 at 06:12:49 UT) before, during and after the GRB with 10s exposures (IR-cut filter only). We observe optical emission at the position given by Swift XRT. start - end comment 6:12:33 - 6:12:43 not visible (>12 mag) 6:12:47 - 6:12:57 visible (~10 mag) 6:13:01 - 6:13:11 max. brightness (~6 mag) Full light curve fill be published later.