Mike, I think you've compressed the site's background image too much for it to serve any purpose. I'd suggest replacing it with a less compressed version or getting rid of it alltogether.
How about running a competition Mike...
"Generate your best background image for IceinSpace."
Conditions
1. It must tile well (ie. join left to right, & top to bottom).
2. It must be less that xxk flie size.
3. Colour restrictions?? do Black & White??
that's the problem with background images.. dimensions have to usually be quite large to avoid it looking too tiled but filesize is an issue. Maybe not worth having. :/