Living in microgravity for an extended period of time can have a significant impact on the human body, as it has evolved to function in Earth's gravity. Astronauts who have spent long periods of time in space have reported issues with their vision and circulation, as well as losses in bone and muscle mass. If you stay in space for a prolonged period, your muscles and bones will become weaker, particularly in the lower back and legs. On Earth, gravity is constantly acting on us, even if we don't consciously think about it.
This means that we are always using the muscles in our lower body to resist it. In space, where gravity is much weaker, there is no need to use your legs to move around or to maintain your posture. As a result, if you stay in space for an extended period of time, your muscles will weaken and your bone mass will decrease. To combat this, research is being conducted to determine the effects of existing drugs on bone loss in space.
In addition, astronauts aboard the International Space Station (ISS) exercise for two hours a day to prevent muscle and bone weakening. Astronauts Scott Kelly and his twin brother Mark have discussed the effects of living in space for a year. They have noted that astronauts can develop stress without even realizing it when they are living and working together in a small space with other astronauts for months at a time. Research has also shown that long periods spent in space can disrupt the immune system and leave astronauts vulnerable to pathogens, hypersensitivity, and unwanted autoimmune responses.
However, with each cosmonaut, astronaut, and commercial space flight that takes place, we are learning more about what to look out for. In space, blood is delivered less forcefully to the body, which can lead to weakened heart muscles and dizziness when standing up. Additionally, it is difficult to predict what could happen to humans if they venture beyond the orbit of the ISS, where the protective properties of Earth's magnetic field are still felt. Space sickness can vary from person to person; some people don't experience it at all.
While Matt Damon did an excellent job portraying life on Mars in his movie, viewers were left wondering how long humans can survive in space. Astronauts aboard the ISS are providing valuable data by comparing their DNA before and after their flight; this helps us understand how their bodies change over time while living in space. The ISS is also expected to serve as a platform for future technologies that will be used in space exploration.