Inside NASA‘s Perseverance rover, there is a device called MOXIE, which stands for Mars Oxygen In Situ Resource Utilization Experiment. MOXIE is the first device that inhales the thin carbon dioxide-rich air of Mars and converts it into oxygen. About the size of a toaster, if built on a larger scale, it could be used not only to provide breathable air for astronauts but also to produce fuel.
Earlier this month, the experiment achieved an important milestone. Researchers pushed MOXIE to double its production. “We got great results” said Michael Hecht, the principal investigator of MOXIE and associate director of the Massachusetts Institute of Technology‘s (MIT) Haystack Observatory in Westford.
“This was the riskiest test we’ve done” Hecht said in an interview. Risky experiment could have damaged the instrument, but that didn’t happen. Record was set on June 6th, operating during the Martian night, and lasted for 58 minutes. Initial requirement for MOXIE was to produce 6 grams of oxygen per hour, a rate that was eventually doubled.
Challenge from the beginning, Hecht added, was to find ways to operate on Mars more efficiently to yield higher amounts of oxygen. Hecht presented a review of MOXIE, detailing a Martian year of usage, at the Space Resources Roundtable meeting.
MOXIE weighs about 18 kg and is designed to transform Martian air through an electrochemical process, separating an oxygen atom from carbon dioxide molecules. The byproduct of the process is carbon monoxide, which can clog the device’s internal parts. Thus, careful monitoring of voltage is required as MOXIE carries out its high-temperature oxygen production.
Next Step is to Increase Production
MOXIE operated seven times during the Martian year 2021. Running one hour at a time, its purpose was to demonstrate the instrument’s capability to work under the diverse conditions Mars experiences during its year. In 2022, MOXIE technicians focused more on the unit’s capabilities and the development of new operational modes. In the previous set of 14 start-stop runs, they added up to 1,000 minutes of operation. “It’s been an exciting journey” Hecht told the audience at the Colorado School of Mines.
But MOXIE is a technology demonstrator, and like many other demonstrators, its long-term life is tied to funding. Funding for MOXIE’s research will end at the end of the year, with the MIT laboratory working to seek new collaborations. As for MOXIE’s future, Hecht stated that the experiment’s results encourage the development of a large-scale system here on Earth.
A version that continuously emits oxygen in an automatic mode could generate 25 to 30 metric tons of oxygen to support a human on a mission to Mars. “It’s all about life. We run an hour at a time. To do this in the future, we’ll need to run for 10,000 hours”.
Understanding how far MOXIE can be pushed before it degrades is important. “On Mars, you don’t get a second chance” Hecht said. “We might turn it up to 12 grams per hour and let it run for a long time”. It will also be important to return in a year, Hecht noted, to check if anything degraded solely due to aging and exposure to the Martian environment.