Question: what is space made of you float in it so there must be something there what is space??

Ian Stephenson answered on 18 Jun 2014:

Space is exactly that – space between stuff. There’s nothing in it (though theoretical physicists construct all sort’s of theoretical stuff to put in there, its really nothing real in any tangible sense). It’s essentially empty.

You “float” in it because there’s no gravity. Strictly speaking its not even floating, as when you float in something its because you’re less dense than the thing you’re floating in (your body is slightly lighter than the same volume of water, so you can swim). But if there’s nothing pulling you down, then you can’t sink – in fact the concepts of up and down don’t even make sense. Without gravity, or some other force to move you, you just stay where you are.