IY UMa superoutburst is due Dear Colleagues, The next superoutburst of the eclipsing SU UMa star IY UMa is due (cf. IBVS 5159). The expected superoutburst in this spring will provide excellent visibility and potentially excellent coverage from the start of the superoutburst. Please keep your close eye on this object as frequently as possible, and inform if any brightening is recognized. Systematic pre-superoutburst time-series observations are also highly encouraged. Regards, Taichi Kato