Staying Alive: Life Support Systems for Future Space Travel
Life support systems ensure that astronauts can live in a comfortable and safe environment, with conditioned air, oxygen, food, water and waste control systems. There are steps that can be taken to make the environment conducive to greater recycling and resource exploitation, all culminating in a closed loop system. This could be, literally, life-changing.
Current life support systems rely on a react and resupply process – for instance, astronauts on board the ISS have to take a limited amount of water with them, because bringing the required amount is impossible, so they rely on regular resupplying; they also depend on packaged food for nutrition as opposed to cultivating food.
Recognising that elements traditionally considered ‘waste’ are in fact resources, will undoubtedly enable longer-term space travel, at a long distance, to enable exploration of the moon and mars.
Space to breathe
Traditional space systems rely on physico-chemical processes, requiring a lot of energy, occurring at particularly high pressures and temperatures. Replacing them with biological processes increases effectiveness and builds the foundation of an entire closed loop system.
Take the air that we breathe as an example. It’s easy to forget that we need 78% nitrogen in the air to avoid ignition of random fires. Research shows that there is extremely little nitrogen on the moon or mars. Producing it through human waste containing high levels of nitrogen is currently an untapped method but a vast resource pool.
This is where micro-organisms come in. Bacteria can produce nitrogen out of human waste in a much more sustainable, long-lasting manner. Nitrogen is required for growing plants and algae as food, or can be converted to nitrogen gas to create an atmosphere. Micro-algae provide a great amino acid source for the astronauts’ diet, replacing the proteins in meat. So, what’s the merit in growing micro-algae?
Both algae and ordinary plants of course produce oxygen through photosynthesis and biomass as well. Many would opt for growing plants to eat, to eventually extract nitrogen from waste, but often this can mean waiting for a couple of months before the plant is ready to eat. With algae, the amount of biomass can double in just a couple of days. Being grown in bioreactors, they are also much more controllable, reacting to light, temperature and nutrient conditions. Aside from this, they are far less prone to disease or being infected by fungi. With plants, avoiding a whole spectrum of diseases is tricky when the slightest variation in conditions can instigate them. The recovery time for plants remains much longer as well.
Bringing the value back to Earth
The value from making improvements to systems in space can be brought back down to Earth, so that everyone can reap the benefits. Bioreactors, containing microalgae, to improve air quality in space can be used for indoor spaces, like offices and meeting rooms. As the CO2 level exceeds optimal amounts, those in the room can begin to fade away and feel their energy alertness sap. Algae can control the CO2 from ambient air to maintain the optimum threshold. The reactors can also be designed into furniture, further contributing to overall wellbeing and becoming part of an office or meeting experience.
Though this may appear niche, already hundreds of people globally are dealing with this expertise and technology. This is despite the fact that the budget for operational, short-term missions is greater. Clearly, the opportunity for longer-term, full-circle scenarios in space is where we are going to find immense, unexploited value, stimulating a chain reaction of benefits across the universe that everyone can enjoy.