The Sound of MOXIE at Work on Mars

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MOXIE (Mars Oxygen In-Situ Resource Utilization Experiment) was launched aboard NASA's Perseverance rover to test a technology for extracting oxygen from the Red Planet's carbon dioxide-rich atmosphere. Audio of MOXIE's air compressor at work on Mars was captured by the microphone on Perseverance's SuperCam instrument on May 27, 2021, the 96th day of the rover's mission.

Since Perseverance landed on Mars in 2021, MOXIE generated a total of 122 grams of oxygen – about what a small dog breathes in 10 hours. At its most efficient, MOXIE was able to produce 12 grams of oxygen an hour – twice as much as NASA's original goals for the instrument – at 98% purity or better. On its final, 16th run, on Aug. 7, 2023, the instrument made 9.8 grams of oxygen. MOXIE successfully completed all of its technical requirements and was operated at a variety of conditions throughout a full Mars year, allowing the instrument's developers to learn a great deal about the technology.

MOXIE produces molecular oxygen through an electrochemical process that separates one oxygen atom from each molecule of carbon dioxide pumped in from Mars' thin atmosphere. As these gases flow through the system, they're analyzed to check the purity and quantity of oxygen produced.

While many of Perseverance's experiments are addressing primary science goals, MOXIE was focused on future human exploration. MOXIE served as the first-ever demonstration of technology that humans could use to survive on, and leave, the Red Planet. An oxygen-producing system could help future missions in various ways, but the most important of them would be as a source of rocket propellant, which would be required in industrial quantities to launch rockets with astronauts for their return trip home.

Rather than bringing large quantities of oxygen with them to Mars, future astronauts could live off the land, using materials they find on the planet's surface to survive. This concept – called in-situ resource utilization, or ISRU – has evolved into a growing area of research.

A key objective for Perseverance's mission on Mars is astrobiology, including the search for signs of ancient microbial life. The rover will characterize the planet's geology and past climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and cache Martian rock and regolith (broken rock and dust).

Subsequent NASA missions, in cooperation with ESA (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.

The Mars 2020 Perseverance mission is part of NASA's Moon to Mars exploration approach, which includes Artemis missions to the Moon that will help prepare for human exploration of the Red Planet.

JPL, which is managed for NASA by Caltech in Pasadena, California, built and manages operations of the Perseverance rover.

For more about Perseverance: mars.nasa.gov/mars2020/