If you haven't heard yet, Japan is planning to throw paper airplanes from the ISS. Reportedly the airplanes will be able to survive re-entry: http://news.bbc.co.uk/2/hi/asia-pacific/7230949.stm Me and my friend were talking about it earlier, and we're at odds as to how exactly Japan will accomplish the throw. Basically, will a normal human powered throw from the ISS provide enough force for the airplane to successfully make it to Earth? Or will the paper airplane simply enter a slightly lower orbit around Earth? There's a few confusing bits in the scenario- 1. Can it be accomplished by throwing the plane straight towards Earth or does it HAVE to be thrown in the opposite direction of motion (thrown backwards)? In either direction, could the throw from a human arm accomplish it? 2. The ISS itself slowly falls to Earth and has to maintain its altitude with regular boosts back up, so I believe the airplane should fall back to Earth no matter how it's thrown or how much force is put in the throw. But what if the ISS was in a perfect geosynchronous orbit, could the plane be successfully thrown to Earth then?