The MOXIE instrument on NASA’s Perseverance rover produced oxygen from Martian carbon dioxide.
MOXIE stands for Mars Oxygen In-Situ Resource Utilization Experiment. It demonstrated the process on April 20, 2021, by taking carbon dioxide from Mars’s thin atmosphere and splitting it through high-temperature solid-oxide electrolysis to produce oxygen.
The achievement was more than a laboratory curiosity. Future human missions could use a larger version of the technology to make breathable oxygen and oxygen for rocket oxidizer, reducing the amount that astronauts would need to transport from Earth. MOXIE was a technology demonstration, not a system capable of supporting a crew.
MOXIE was housed aboard Perseverance, which landed in Jezero crater in February 2021. The rover’s other instruments had different jobs: SHERLOC studied minerals and organic molecules, RIMFAX examined subsurface structure with radar, and Mastcam-Z provided stereo imaging and geological context. MOXIE completed its operational campaign in 2023 after repeated production runs.