‘Historic’ Box That Produced Oxygen at the Speed ​​of a Tree on Mars

When NASA’s robotic Perseverance rover flew to Mars last year, it brought a small, golden box called MOXIE for the Mars Oxygen In-Site Sourcing Experiment.

Since then, MOXIE has been producing oxygen from thin Martian air.

And in the journal Science Advances Wednesday, the team behind this mechanism confirmed that MOXIE works so well that its oxygen output is comparable to the output rate of a modest Earth tree.

At the end of 2021, extensive data showed that MOXIE successfully achieved a target output of six grams per hour of oxygen during seven separate experimental runs and under various atmospheric conditions. This includes day and night, different Martian seasons, and so on.

“The only thing we haven’t shown is running at dawn or dusk, when the temperature changes significantly,” said Michael Hecht, principal investigator for the MOXIE mission at Massachusetts Institute of Technology’s Haystack Observatory. said in a press release. “We have an ace at our disposal that will allow us to do that, and when we test it in the lab, we can reach that final milestone to show that we can really run at any time.”

For scientists and space agencies, it’s particularly exciting that MOXIE’s word is strong, as proposed timelines for astronaut-laden Mars expeditions have upcoming deadlines for learning how to keep future red planet space explorers safe.

SpaceX CEO Elon Musk’s goal to land humans on Mars is 2029, for example, and it seems like NASA’s own goal. upcoming Artemis I lunar mission To pave the way for Mars trips Planned for the 2030s or 2040s. “To support a human mission to Mars, we need to bring a lot of things from Earth, like computers, spacesuits, and habitats,” Jeffrey Hoffman, MOXIE assistant principal investigator and professor at MIT, said in a press release. Said. “But stupid old oxygen? If you can get there, go – you’re way ahead of the game.”

In its current form, the MOXIE is super small (basically the size of a toaster), but that’s potentially a good thing. This means that if scientists can somehow increase the size of the patterned cube, MOXIE could produce much more than just six grams per hour.

“We’ve learned a tremendous amount that will inform future systems on a larger scale,” Hecht said.

Maybe one day, the researchers say, it could eventually produce oxygen at the rate of a few hundred trees so that they could feed the astronauts when they got to Mars and fuel the rockets that require the life-giving element to bring the crew back to Earth.

“Astronauts who spend a year on the surface will use maybe a metric ton in between,” Hecht said in a NASA press release last year. But, by the space agencyRemoving four astronauts from the Martian surface on a future mission will require approximately 15,000 pounds (7 metric tons) of rocket fuel and 55,000 pounds (25 metric tons) of oxygen. Bringing all that oxygen from Earth would be extremely costly and inefficient.

So, as Hoffman says, why not make all the oxygen on the arid planet itself?

How does MOXIE work?

On Mars, MOXIE actively converts carbon dioxide in the Martian atmosphere, of which the element makes up 96%, into respirable oxygen.

A bit of chemistry 101 is that carbon dioxide molecules are made up of one carbon atom and two oxygen atoms. These bits are basically stuck together. But an instrument aboard MOXIE, called the Solid Oxide Electrolyzer, can somehow collect the oxygen particles inside these CO2 molecules, which scientists are interested in. Once complete, all the free-floating oxygen particles are recombined into O2, molecules with two oxygen atoms known as the oxygen species we know and love.

I know it’s different, but when I do this, I think of Pixar’s WALL-E. So, as WALL-E said: Ta-da!

“This is the first demonstration of actually using resources on the surface of another planetary body and chemically converting them into something that could be useful for a human mission,” Hoffman said. Said. “History in that sense.”

Along the way, this process requires the use of super-high heat, which reaches temperatures of around 1,470 degrees Fahrenheit (800 Celsius), fascinatingly giving MOXIE its characteristic gold finish.

Like NASA’s groundbreaking James Webb Space Telescope, MOXIE must be shielded from infrared heat because it works with heat. Gold plating does just that, and in fact JWST’s mirrors are also gold plated for exactly that reason.

In the next step, the MOXIE team aims to demonstrate that the MOXIE works well under even more intense conditions, such as the next run during “highest intensity of the year,” Hecht said. “We’re going to put everything as high as we dare and let it run for as long as we can.”