Can we create a self-sustaining space station, now or in the near future? Benjamin Kustrin Space stations are of huge importance to reaching out further in space exploration, but having a self-sustaining one could be potentially even better. In this project, I will discuss four main points – the benefits of having a self-sustaining space station, the engineering problems of making such a station, and considering both of these, is it feasible to create a self-sustaining space station, now or in the near future. The benefits of a self-sustainable space station Quoting NASA, the creators of the ISS (International Space Station) the purpose of a space station is to make it “possible for people to have an ongoing presence in space ... allow crew members to do research that could not be done anywhere else ... [and] to prepare for human missions that reach farther into space than ever before.”1 These main goals are already partially met by current space stations, the ISS, and the Tiangong Space Station. The ISS has continuously been inhabited by humans for more than 21 years 2, completing the first goal. The second goal, completing research that could not be done anywhere else, is being completed, shown by some of the experiments, for example ISS-RapidScat, which uses its unique position in orbit for mapping large areas with microwaves to predict weather patterns (900 km scanning radius3 compared to the range limit of similar ground-based versions which is a single spot4). It can also prepare for human missions into deep space, at least in part, by being a technology demonstrator for future outposts such as the planned Gateway station, which will be a “staging point for deep space exploration5”. If a non-self-sustainable space station can do all of that, why need a selfsustainable one? Self-sustainable space stations have a few significant advantages. Revisiting the first goal, a self-sustaining space station would not only allow an ongoing presence in space, but it would also allow humanity to survive, should Earth be destroyed by a war or asteroid, as a selfsustaining space station would not require supplies from Earth. The second goal, allowing crew members to do research that could not be done anywhere else, would be even cheaper on a station whose payload can be filled entirely with experiments and not just supplies. Finally, the third goal, which is to prepare for deep space human missions, would also be improved by a large, self-sufficient station as one could utilise the large station as a ‘orbital construction shipyard’ for flights to Mars and beyond, as well as training astronauts to spend longer periods in space. Engineering of such a station To be completely self-sufficient is to “able to maintain oneself or itself without outside aid” 6. When considering how to, we should take account the resources needed to keep a person alive. NASA7 states that “Human beings have certain basic needs. We must have food, water, air, and shelter to survive.” Considering this, we should think about ways we can create them. Our system will be based around the most important: air and its production. Air production One way to make oxygen, in a small space and with few moving parts or dependencies on plants and their survival, is a process involving Electrolysis and the Sabatier reaction. This process is currently being demonstrated on the ISS8 to produce breathable air, with this formula: 2H2O >electrolysis> O2 + 2H2 >respiration> CO2 + 2H2 + 2H2 >Sabatier reaction> 2H2O + CH4
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