The experiment is part of NASA Perseverance-Mission-Rover The February 2021 landing on Mars is the first time resources from another planet have been converted into something useful for human missions, the researchers said. The little box, developed by NASA’s Jet Propulsion Laboratory and the Massachusetts Institute of Technology, produces enough oxygen to match the output of a small tree on Earth, and can do so day and night during Mars’ multiple seasons.
“That’s what explorers have been doing since time immemorial,” said Jeffrey Hoffman, a former NASA astronaut and deputy principal investigator on the MOXIE mission and a professor of aeronautical engineering at MIT. “Find out what resources are available where you’re going and learn how to use them.”
Space agencies, scientists and entrepreneurs are urging people to explore Mars. NASA’s long-awaited and turbulent Artemis mission to the Moon is a stepping stone to Mars exploration over the next decade or so. China hopes to bring humans to this planet 2033. Elon Musk, the world’s richest person and CEO of SpaceX, has hinted as much 2029.
Hoffman said that getting humans to Mars requires several complicated things. Astronauts have to endure high levels of cosmic rays during the long journey to the planet. The journey to and from Mars might take more than 8 months, so space travelers should have plenty of food and medicine.
Perhaps the most important thing is a reliable supply of oxygen, Hoffman said. Astronauts need it to breathe in any temporary habitat they have set up on Mars, as well as in space suits when exploring the planet. Providing the rocket with the fuel it needs to return to Earth from Mars is also an important motive.
Hoffman said space agencies might send enough oxygen to Mars for astronauts to breathe and make the journey home, but that would be very expensive because it would require multiple rocket launches. It would be cheaper to make oxygen on Mars from carbon dioxide in the atmosphere, he said. The atmosphere of Mars consists of 96% carbon dioxide.
To test its ability to turn carbon dioxide into oxygen, NASA brought a small gold chest onto the Perseverance rover mission last year. Since April 2021, MOXIE has conducted multiple tests during which it produced oxygen at different times of the Martian day and under different seasonal conditions. During each experiment, the box produced approximately 6 grams of oxygen per hour, equivalent to the output of a modest tree on Earth. (In his most recent test, to be published in a future publication, Hoffman said machine production has increased to 10 grams per hour.)
As the technology is perfected, scientists will need to scale up the machine dramatically and ensure it can run continuously. To sustain a manned mission to Mars and bring people back, it needs to generate at least 4.5 to 6.5 pounds of oxygen per hour over a multi-year mission, Hoffman said. “It would take several hundred times longer,” he said.
The machine can be operated during most parts of the Martian day, with the exception of a few specific times.
The only thing we didn’t show is running at dawn or dusk when the temperature rises [on Mars] “It’s changing dramatically,” said Michael Hecht, principal investigator on the MOXIE mission at MIT’s Haystack Observatory. “We’ve got an ace up our sleeve that lets us do that, and once we’ve tested that in the lab, we can achieve that final feat to show that we really can walk anytime.”
Engineers plan to push the MOXIE instrument to its limits, increasing its oxygen production capacity and ensuring it operates during the Martian spring, when the planet’s atmosphere is dense and carbon dioxide levels high. “We will set everything as high as we dare and let it go as long as possible,” said Hecht.
Engineers will monitor the machine for wear and tear and see if it can withstand enough stress to suggest it can be converted into a full-fledged system that can run for thousands of hours continuously. If so, the impact might be significant.
“To support a manned mission to Mars, we need to bring a lot of stuff from Earth,” Hoffman said. “But stupid old oxygen? If you can do it, keep it up – you’re way ahead of the game.”
