Chapter 9: Life Support Systems

1. Ecosystem Module

The life support system will include a closed ecosystem module, which in addition to being installed on passenger-filled spacecraft, can also be transported via containers and assembled on Mars. This ecosystem will support plant growth, provide food and oxygen, and process waste. Part II: Establishment — Closed Life Support System: A Closed Life Support System (CLSS) is a key technology for ensuring human survival during long-duration space missions or in extraterrestrial environments. Such systems simulate Earth's environment, providing the required air, water, food, temperature and humidity control, and waste processing functions without relying on external resources. Multiple closed life support system experiments have been conducted to verify the feasibility and long-term stability of such systems in extreme environments.

1. BIOS-3 Experiment

BIOS-3 was a closed life support system experiment conducted by the Soviet Union from the late 1970s to the early 1980s. This experiment was conducted in a sealed chamber in Siberia, with a laboratory simulating an Earth-like ecological environment in a closed-loop system. The experiment lasted multiple cycles, with each cycle lasting up to 180 days. During the experiment, four participants were placed in the sealed space, relying on the system for air, water, and food, while the system processed waste. Through this experiment, scientists were able to collect substantial data, verify the stability of the biological cycling system, understand human physiological responses in closed environments, and gain deeper insights into waste processing and resource recycling. 2. Life Support Cabin Experiment (Mars500): Mars500 was a Mars mission simulation experiment conducted by Russia and international partners, aimed at providing key data for future Mars exploration missions. The experiment was conducted between 2007 and 2011, with participants living in a completely closed environment simulating the isolation and delayed communication of a Mars mission. The experiment lasted 520 days, during which six volunteers lived in a Mars-cabin-like environment, relying on the system for air, water, and food. The system tested not only air and water recycling but also conducted in-depth analysis of waste processing and psychological adaptation. Mars500 provided valuable experience for understanding the technical challenges and human behavior during long-duration Mars missions.

3. NASA's CHRIS Experiment

NASA's CHRIS (Closed Loop Life Support System) experiment aimed to develop closed life support systems suitable for Mars missions. This experiment combined gas exchange, water recovery, waste processing, and other technologies, simulating a completely closed environment to verify the effectiveness of different technologies during long-duration missions. The CHRIS experiment included not only water and air recycling but also food cultivation systems, exploring how to produce food and other resources in space to reduce dependence on external supplies. Through this experiment, NASA further optimized air purification technology, carbon dioxide removal technology, and water resource recovery systems.

4. MELISSA Project

The MELISSA (Micro-Ecological Life Support System Alternative) project is a long-term experiment conducted by the European Space Agency (ESA) aimed at developing a fully autonomous bio-regenerative life support system. The core of this project lies in utilizing the interactions among microorganisms, plants, and animals to form a closed ecosystem that maintains the gases, water, and food resources needed for human life. The innovation of the MELISSA experiment lies in its use of the synergistic effects of microorganisms and plants, which can not only recycle waste but also extract valuable resources (such as food and oxygen) from it, providing reliable support for long-duration space missions. In the experiment, the system ensures efficient resource cycling through biological processing and AI monitoring. 5. Japan's Kibo Experiment: Japan has also conducted closed life support system-related experiments on the International Space Station (ISS), the most famous being the Kibo experiment module. The Kibo module is part of the ISS, equipped with multiple life support technologies aimed at supporting long-duration space exploration missions. The water processing and air conditioning systems in the Kibo experiment use advanced technology capable of generating oxygen through water electrolysis and recovering carbon dioxide through physical and chemical processes. Additionally, the experiment studied how to use plant cultivation systems to provide fresh food for astronauts and conduct waste recycling. These technologies have played an important demonstration role for resource cycling and life support systems in closed environments.

2. Water and Air Circulation

The water and air circulation systems within the life support system will ensure efficient resource utilization. The water circulation system will include advanced filtration and purification technologies, while the air circulation system will provide fresh air and maintain suitable climate conditions. First, one of the key technologies in the water circulation system is advanced water recovery and purification equipment. Water resources at the Mars base primarily rely on water circulation, and all water usage (such as drinking water, washing water, etc.) needs to be recovered through processing. The water recovery system uses efficient physical, chemical, and biological filtration technologies to remove impurities, microorganisms, and harmful substances from water. A typical approach uses multi-stage filters, including activated carbon, reverse osmosis membranes, UV disinfection, and chemical treatment technologies to ensure water quality meets drinking standards. Additionally, the system employs distillation and condensation technologies to recover all wastewater at the base, including human waste, converting it through technical means into safe drinking water and clean water. To improve water recovery efficiency, self-cleaning equipment can also be used, such as combining plant and microbial treatment technologies in the water circulation process, further purifying water through a "wetland system." This system utilizes plant roots to absorb nutrients and harmful substances from water, while microorganisms decompose organic pollutants, forming an ecological closed loop that improves water quality. The air circulation system is responsible for providing fresh oxygen, removing carbon dioxide and other harmful gases, and maintaining appropriate oxygen concentration and temperature/humidity. Air processing equipment typically includes air purifiers, oxygen generators, and carbon dioxide removal devices. Oxygen generators primarily produce oxygen by electrolyzing water, decomposing water into hydrogen and oxygen to supply sufficient oxygen for breathing. Carbon dioxide removal devices use chemical adsorption technology to absorb and convert carbon dioxide, maintaining safe levels of oxygen content and carbon dioxide concentration in the air. The air circulation system also includes temperature and humidity regulation devices to ensure suitable environmental conditions. For example, heat exchangers and cooling systems regulate internal temperatures, while humidity control systems maintain appropriate humidity levels. These systems can simulate Earth's natural climate environment, improving comfort and reducing health risks. Experiments and research show that integrated water and air circulation systems can effectively maintain life support in closed environments, especially during long-duration habitation missions, ensuring efficient resource utilization and conservation while reducing dependence on external resources. As Part II: Establishment — technology continues to advance, future circulation systems will become more efficient and intelligent, capable of adapting to the challenges of different interstellar environments, providing reliable support for humanity's space exploration and interstellar immigration.

3. Waste Processing and Recycling

The waste processing system will include biodegradation units and recycling equipment, which can be pre-loaded in containers and put into operation immediately after base assembly. First, the core of the waste processing system is the biodegradation unit. The living environment of the Mars base is closed and resources are limited, so organic waste needs to be processed through biotechnology. This waste primarily comes from food residues, plant waste, etc. The biodegradation unit uses a series of microbial and enzymatic degradation processes to decompose organic waste into simple chemical components such as water, carbon dioxide, and organic fertilizer. These microbial processing systems can be customized according to the type and composition of waste to ensure processing efficiency and safety. For example, anaerobic digestion technology can be used to produce methane gas through microbial decomposition under anaerobic conditions, providing energy for the base. Additionally, waste recycling equipment will work closely with the biodegradation unit to ensure all resources are fully utilized. The waste recycling system mainly includes classification and processing equipment for metals, plastics, glass, and other recyclable items. This equipment will use advanced automation technologies such as sensors, sorting robots, and robotic arms to classify and process various types of waste. Through classification and recycling, reusable resources at the base (such as metals, plastics, glass, etc.) can re-enter the production and living systems, achieving closed-loop resource cycling. Metals and plastics will be reused through smelting and reprocessing technologies, reducing the need for external resources. For non-organic waste such as paper and chemical waste, recycling equipment uses advanced chemical processing methods. For example, paper can be decomposed into fibers and other chemical components through chemical reduction processes for reuse. Chemical waste requires specialized processing equipment to safely convert it into harmless substances. All waste processing will be subject to strict monitoring to ensure no harmful substance residues remain. Experimental data shows that through the combination of biodegradation and efficient recycling, over 99% of waste in a closed base can be processed and recycled, which not only reduces waste accumulation and maintains ecological stability but also maximizes the use of limited resources. Additionally, optimized waste processing systems can promote plant growth by providing organic fertilizer, further supporting the sustainable development of the base.