Fireworks image doesn't load in Firefox

The image on my home page loads fine in IE but it is completely
invisible in Firefox. The image source is a fireworks doc (png) and I
can't figure out why it isn't loading. The image isn't a broken link
and even the drop-down menus off the image work fine. Any idea what is
wrong? Check out the site:

www.cosmos.ucdavis.edu/test.html