Space medicine is the science in which we do the practice of medication on astronauts in the atmosphere outside the earth. Astronautical hygiene is the application of knowledge and skill to the avoidance of exposure to the risks that may be the origin of astronaut ailing health. These two sciences work jointly to make sure that astronauts work in a secure atmosphere. It is important to know that for how much duration people can endure the space environment without getting a disease and how much time they will take to have the adaptation to the earth's environment. Environment on space is...