function popup(){
	var x = (screen.width - 407) /2;
	var y = (screen.height - 486) /2;

	miradores = window.open("mapa.php","miradores","status=0,toolbar=0,menubar=0,directories=0,resizable=0,scrollbars=0,width=407,height=486"); 
	miradores.moveTo(x,y);
}