Arthrospira C, an instrument designed and built by Redwire for the European Space Agency (ESA), uses cyanobacterium Arthrospira sp. strain PCC8005, commonly known as Spirulina, for carbon dioxide and nitrate removal, along with oxygen and biomass production. On November 2024, Arthrospira C launched to the International Space Station (ISS) onboard SpaceX-31. The instrument is being used for an investigation focused on advancing the development of spacecraft life support systems and fresh food production in space. Following launch, Arthrospira C was successfully installed on the ISS by NASA astronaut Nick Hague prior to beginning operations. 

Following installation, the Spirulina was cultured in the instrument’s four bioreactors at a continuous steady state regime and kept at a constant predefined cell density. Arthrospira C operated non-stop for a few weeks in the Biolab facility. During this time, the science teams were able to monitor all biological changes of the bacterium. The oxygen produced by the Spirulina was released directly into ISS, giving the astronauts onboard a fresh breath of air produced by Arthrospira C. It also reached a historic milestone: the first bioreactor to operate for more than five weeks in space. Arthrospira C is still producing oxygen, with four more weeks to go. 

Following successful on-orbit operations, four Arthrospira C reservoirs have returned to Earth, where scientists will further study the samples. The results from the latest investigation could help advance new technologies for oxygen production and other life support systems needed for long-duration space travel. 

Want to learn more? You can read about Arthropsira C and other Redwire technology that launched to the ISS on SpX-31 here.