I want to know whether a person can float in the space just 100 km above the earth's surface. If we would float, what are the factors that make us float? And if we don't, what are the factors that keep us from floating in the space? Those object need to orbit around earth at high speed like international space station to keep us floating or is it enough to move along earth's speed of rotation? I would like to give you an example to tell what I actually want to know about. It is like this that I have taken a big air-tight box that has enough air for a rat to survive for 10 days, tied some Helium balloons to it and tied a rope of length 105 km to the box. Now I left the box up and allowed it go as high as 105 km (the length of the rope) while anchoring the other end of the rope on the earth. Now the question is will the Rat in the box float??? If yes, why will it float?? If no, why won't it float??