var Ads = 3;
var now = new Date();
var sec = now.getSeconds();
var ad = sec % Ads;
ad +=1;

if (ad==1) {
URL="sierralarana.com/astronomy.php";
BG="slr_astro_news_banner@240x120";
ALT="Sierra La Rana";
}

if (ad==2) {
URL="flytranspecos.com";
BG="ftp";
ALT="Fly Trans Pecos! Support the Trans Pecos Air Initiative!";
}

if (ad==3) {
URL="sierralarana.com";
BG="slr";
ALT="Sierra La Rana";
}




document.write('<A href=\"http://www.' + URL + '\" target=\"ads\"><img src=\"http://www.virtualbigbend.com/images/' + BG + '.jpg\" alt=\"' + ALT + '\" width=\"120\" border=\"0\"></a>');

if (navigator.Appname=="Internet Explorer"){
   alert('Sorry! You cannot view the banners on this site with Internet Explorer!');
}