var currentDate  = new Date();
var x = currentDate;
currentDate.setTime(currentDate.getTime() + (currentDate.getTimezoneOffset()*60000));
var blueMoonDate = new Date(96, 1, 3, 16, 15, 0);
var lunarPeriod  = 29*(24*3600*1000) + 12*(3600*1000) + 44.05*(60*1000);
var moonPhaseTime = (currentDate.getTime() - blueMoonDate.getTime()) % lunarPeriod;
var time = Math.round((lunarPeriod-moonPhaseTime)/(24*3600*1000));
document.write("<strong>");
document.write("Der n&auml;chste Vollmond ist in ",time," Tag");
if (time > 1) document.write("en");
if (time < 1) document.write("en");
document.write("!</strong>");