Living in a house is not similar to living on Earth. In space, the bodies of astronauts modify. On Earth, our lower body and legs carry our weight. This helps keep our bones and muscles robust. In space, astronauts float. They try not to use their legs as much. Their lower backs begin to lose strength. Their leg muscles do too. The bones begin to urge weak and skinny. This is often terribly dangerous for astronauts’ bodies.