Algae are present in salt and in fresh water all over the planet including in unexpected places. They are very robust organisms and are able to grow in a wide range of milieu: very high salinity, very high UV, dryness, extreme temperature or, extreme pH. Algal metabolism can undergo extreme environments and have multiple uses. This is why algae are very good candidates for life support systems in space or on celestial bodies.
While the crew is breathing and producing C02, algae exchanges CO2 to O2 in a controlled ecological life support system while they perform photosynthesis. This exchange is very efficient: algae are one of the main oxygen producers on Earth. A good example is the Chlamydomonas reinhardtii.
Some algae such as Spirulina are highly nutritive, full of protein and vitamins. It is actually already available on the market in the form of tablets and pills. Spirulina could be used in astronaut food to help ensure they keep a nutritious and balanced diet. This year at the International Space Univeristy (ISU), Phillippa participated in a study about astronaut acceptability of algae as a food supplement. Since astronauts are from many different countries, this included a food tasting involving people from many different cultures to assess their level of acceptability.
Furthermore, algae have a high potential for producing biofuel and filtering water. Algal metabolisms need light (power supply), water, nutrients and C02 for performing photosynthesis and growing in a space-bioreactor.
In association with bacteria, Chlorella vulgaris could contribute to degrade astronaut’s urea. Thanks to chemical reactions, algae uses CO2 and elements present in the ureain order to clean urea. Chlorella vulgaris, could also produce biofuel thanks to its high lipid content.
Food, oxygen, fresh water, biofuel… Algae look like a very promising culture for space exploration. Like a large range of space technologies, space algae might take place in your daily life…maybe sooner than you expected.
Because we are all Born For Space!