function showMoon() {
var size = 20; /* velkost vykresleneho Mesiaca */
var height=1;
var i;
var currentDate  = new Date();
var x = currentDate; /* nastavi aktualny datum */
	currentDate.setTime(currentDate.getTime() + (currentDate.getTimezoneOffset()*60000)); /* a aktualny pasmovy cas */
var blueMoonDate = new Date(96, 1, 3, 16, 15, 0); /* tu je pociatocny spln Mesiaca (v UT) */
var lunarPeriod  = 29*(24*3600*1000) + 12*(3600*1000) + 44.05*(60*1000); /* perioda */
var moonPhaseTime = (currentDate.getTime() - blueMoonDate.getTime()) % lunarPeriod; /* aktualna faza */
var percentRaw = (moonPhaseTime / lunarPeriod); /* aka cast Mesiaca je osvetlena? */
var percent    = Math.round(100*percentRaw) / 100;
var percentBy2 = Math.round(200*percentRaw);
var left  = (percentRaw >= 0.5) ? "mesiac_c.gif" : "mesiac_b.gif";
var right = (percentRaw >= 0.5) ? "mesiac_b.gif" : "mesiac_c.gif"; 
document.write('<div align="center">') /* toto vykresli aktualnu fazu */
	if (percentBy2 > 100) {
		percentBy2 = percentBy2 - 100
		}
	for (i = -(size-1); i < size; ++i) {
		var wid=2*parseFloat(Math.sqrt((size*size)-(i*i)));
		if (percentBy2 != 100)
			document.write ('<img src="images/' +left + '" height="1" width="' +(wid*((100-percentBy2)/100))+ '">')
		if (percentBy2 != 0)
			document.write ('<img src="images/' +right+ '" height="1" width="' +(wid*((percentBy2)/100))+ '">')
		document.write ('<br>')
	}
document.write('</div>');
}