NASA has completed the MOXIE (Mars In Situ Oxygen Resource Utilization Experiment) device, which has been far more successful than its developers at the Massachusetts Institute of Technology (MIT) had hoped. When the first astronauts land on Mars, they may owe the air they breathe and the rocket fuel to get them home to a device the size of a microwave oven.
“The impressive performance of MOXIE proves that It is possible to remove oxygen from the atmosphere of Mars, which could help provide future astronauts with breathing air or rocket fuel,” said NASA Deputy Administrator Pam Melroy. “Developing technologies that allow us to harness resources on the Moon and Mars is critical to building a long-term lunar presence, creating a resilient lunar economy, and supporting an initial human exploration campaign on Mars.”
Since Perseverance landed on Mars in 2021, MOXIE has produced a total of 122 grams of oxygen, about what a small dog breathes in 10 hours. At peak efficiency, MOXIE was able to produce 12 grams of oxygen per hour (twice what NASA’s original goals were for the instrument) with a purity of 98% or better. On its sixteenth pass on Aug. 7, the instrument produced 9.8 grams of oxygen. MOXIE successfully met all the technical requirements and operated on Mars for a whole year under various conditions, allowing the instrument’s developers to learn a lot about the technology.
“We are proud to have supported an innovative technology like MOXIE that could convert local resources into useful products for future exploration missions,” said Trudy Kortes, director of technology demonstrations at the Space Technology Mission Directorate (STMD) at NASA Headquarters. NASA in Washington is funding the MOXIE demonstration. “By testing this technology under real conditions, We’re one step closer to a future where astronauts “live off the land” on the Red Planet.
MOXIE generates molecular oxygen through an electrochemical process that separates an oxygen atom from each carbon dioxide molecule pumped up from the thin Martian atmosphere. As these gases flow through the system, they are analyzed for purity and the amount of oxygen produced.
While many of Perseverance’s experiments address the mission’s main scientific goals, MOXIE has focused on future human exploration. MOXIE served as the first demonstration of a technology humans could use to survive and get off the Red Planet. An oxygen production system could support future missions in many ways, but the most important of these would be as a source of rocket fuel, which would be needed in industrial quantities to launch rockets carrying astronauts on their journey home.
Instead of bringing huge amounts of oxygen to Mars, future astronauts could live off land and use materials they find on the planet’s surface to survive. This concept, referred to as in situ resource utilization, or ISRU, has become a growing area of research.
“MOXIE has clearly served as an inspiration to the ISRU community,” said the instrument’s lead researcher, MIT’s Michael Hecht. “It showed that NASA is willing to invest in such future technologies. And it was a flagship that impacted the exciting space resource industry.”
The next step would not be building MOXIE 2.0, although Hecht and his team have learned a lot about how to design a more efficient version of the instrument. Rather, it would be better to build a large-scale system that includes an oxygen generator like MOXIE and a way to liquefy and store that oxygen.
Above all, however, Hecht would like other technologies to be used on Mars. “We have to make decisions about what things need to be validated on Mars,” Hecht said. “I think there are a lot of technologies on that list; I am very happy that MOXIE was the first.”
A key objective of the Perseverance mission to Mars is astrobiology, including the Search for traces of ancient microbial life. The rover will characterize the planet’s past geology and climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and stockpile Martian rock and regolith (fractured rock and dust).
Subsequent NASA missions, in cooperation with ESA (the European Space Agency), would send spacecraft to Mars to collect these sealed samples from the surface and return them to Earth for in-depth analysis.
NASA’s Jet Propulsion Laboratory (JPL), managed for the agency by Caltech in Pasadena, California, built the Perseverance rover and manages operations. JPL manages the MOXIE project for the Technology Demonstration Missions program within STMD. MOXIE was also supported by NASA’s Exploration Systems Development Mission Directorate and Science Mission Directorate.
