Micro-Ecological Life Support System Alternative
Over 30 years of R&D done by the European Space Agency and its partners to develop a completely closed-loop life support system that is nearly 100% efficient and does not require resupplying. Intended for future use in deep space exploration where resupply trips will not be possible. To sustain a manned mission to Mars without recycling would require approximately 30 tonnes of supplies, so recycling is vital to the success of future missions.
“Essentially, we are trying to duplicate the main functions of Earth’s ecosystem, without the huge atmosphere, ocean and soil buffers.”
Christophe Lasseur, head of melissa project
The compartmentalized structure of MELiSSA includes 5 main compartments; 3 of which breakdown waste by fermentation, the 4th where algae and plants are grown to produce food, oxygen, and water, and the 5th being fitted for crew living. Currently their pilot plant houses mice in the 5th compartment.
MELiSSA is a huge step up from the current recycling system used on Mir on the ISS which is currently capable of purifying water, recycling urine and exhaled carbon dioxide. Non-recycled waste is either burned upon reentry if solid or vented overboard if gaseous, whereas MELiSSA is designed to use all waste to produce everything necessary to sustain human life.
“Understanding and recreating an ecosystem in which humans can survive could benefit people who live in less affluent places where water or even clean air is sparse – regardless of whether these people are colonising a distant planet or living in a desert on Earth.”
ESA
Nitrification
MELiSSA transforms urine to the production of food by their process of nitrification. Urine is stabilized, so that is does not become a risk to astronauts, then it is transformed to the proper substrate to them be used for plants and micro algae cultivation. Challenges in this process arise in terms of space adaptation with the unknown effects of cosmic radiation and need for gravity-independence.
Sources: ESA. (2009, June 5). Life support pilot plant paves the way to Moon and beyond. Retrieved September 26, 2020, from https://www.esa.int/Enabling_Support/Space_Engineering_Technology/Life_support_pil ot_plant_paves_the_way_to_Moon_and_beyond
ESA. (2014, April 16). Life support. Retrieved September 26, 2020, from https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/Research/Life_support
ESA. (2019, April 5). A decade-long quest to build an ecosystem in a room. Retrieved September 26, 2020, from https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/Research/A_decade-long_quest_to_build_an_ecosystem_in_a_room
MELiSSA Foundation. (n.d.). Nitrification. Retrieved September 26, 2020, from https://www.melissafoundation.org/page/nitrification