A robot the size of a lunchbox has been making oxygen on Mars since February 2021.
MIT says that its Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE) was deployed as part of NASA’s Perseverance rover mission. In the year-and-a-half since, "MOXIE was able to produce oxygen on seven experimental runs, in a variety of atmospheric conditions, including during the day and night, and through different Martian seasons," MIT says in a news release.
MOXIE currently produces approximately six grams of oxygen per hour, which MIT compares to "a modest tree on Earth." (It's unclear how much a particularly braggadocious tree produces.) But a larger version of the device should be able to pump out even more oxygen—and even this relatively small amount could be an important breakthrough in the quest to explore Mars.
"The current version of MOXIE is small by design, in order to fit aboard the Perseverance rover, and is built to run for short periods, starting up and shutting down with each run, depending on the rover’s exploration schedule and mission responsibilities," MIT says. "In contrast, a full-scale oxygen factory would include larger units that would ideally run continuously."
It's not like a single tree provides all of the oxygen on Earth, either, and few trees fit in lunch boxes. It makes sense that machinery capable of producing oxygen on Mars would also have to be fairly big—or at least bigger than the current iteration of MOXIE—and capable of operating continuously to be a viable candidate for providing breathable air on the Red Planet.
"To support a human mission to Mars, we have to bring a lot of stuff from Earth, like computers, spacesuits, and habitats," MOXIE deputy principal investigator Jeffrey Hoffman said in a statement. "But dumb old oxygen? If you can make it there, go for it—you’re way ahead of the game."
Additional information about MOXIE is available via an article, "Mars Oxygen ISRU Experiment (MOXIE)—Preparing for human Mars exploration," published by Science Advances on Aug. 31.