Personally I don’t like that pixelfont… never have. But… aside from that. When you click on a link to start the transition I think would look a lot better if it was smoother.
After the transition is done… Home and Credits are soooo close to your nav border, might want to bump them down.
When you activate a section I’ve noticed that you still get the hand when you hover over the button of the section that is activated, I would consider taking that off.
The darker grey part under the main part is really choppy, I can’t tell what’s supposed to be going on. Looks like an inset, or a far shadow… doesn’t really fade off well. With that you should make the edge sharp and not blurred too.
Maybe bump up the words international space station at the top up 1 or 2 px
Really good site, nice transitions, the concept is right on key too, only minor things IMO.