When NASA’s Perseverance robotic rover left for Mars last year, it carried with it a small golden box called MOXIE, for the In-Situ Martian Oxygen Resource Utilization Experiment.
Since then, MOXIE has been making oxygen from the thin Martian air.
And on Wednesday in the journal Science Advances, the team behind the contraption confirmed that MOXIE has been working so well, in fact, that its oxygen production is comparable to the production rate of a modest terrestrial tree
By the end of 2021, extensive data showed that MOXIE successfully achieved its target oxygen production of six grams per hour during seven separate experimental runs, as well as under a variety of atmospheric conditions. This includes day and night, different Martian seasons, and the like.
“The one thing we haven’t demonstrated is running at dawn or dusk, when the temperature is changing substantially,” said Michael Hecht, principal investigator of the MOXIE mission at the Haystack Observatory at the Massachusetts Institute of Technology. in a press release. “We have an ace up our sleeve that will allow us to do that, and once we test it in the lab, we can reach this final milestone to show that we really can run at any time.”
This is where MOXIE is on the Martian rover.
NASA
For scientists and space agencies alike, it’s especially exciting that MOXIE’s promise is strong, because proposed timelines for astronaut-laden Mars expeditions have deadlines for learning how to keep future space explorers safe on the planet red
SpaceX CEO Elon Musk’s goal of landing humans on Mars appears to be 2029, for example, and NASA’s upcoming Artemis I moon mission is intended to pave the way for Mars excursions planned for the 2030s or 2040s. “To support a human mission to Mars, we need to bring a lot of things from Earth, such as computers, spacesuits and habitats,” said Jeffrey Hoffman, MOXIE deputy principal investigator and professor from MIT, in a press release. “But stupid old oxygen? If you can get there, go for it, you’re way ahead of the game.”
As it is, MOXIE is very small (it’s basically the size of a toaster), but that’s potentially a good thing. It means that if scientists can somehow increase the size of the printed cube, MOXIE could produce much more than just six grams of oxygen per hour.
“We’ve learned an enormous amount that will inform future systems on a larger scale,” Hecht said.
Perhaps one day, the researchers say, it could produce oxygen at the rate of several hundred trees, sustaining astronauts once they reach Mars and fueling rockets that require the vital element to get crew back to Earth.
“Astronauts who spend a year on the surface will probably use a metric ton between them,” Hecht said in a NASA press release last year. But getting four astronauts off the Martian surface on a future mission would require roughly 15,000 pounds (7 metric tons) of rocket fuel and 55,000 pounds (25 metric tons) of oxygen, according to the space agency. Bringing all that oxygen from Earth would be very expensive and inefficient.
So, as Hoffman says, why not make all the oxygen from the barren planet itself?
How does MOXIE work?
On Mars, MOXIE is actively converting the carbon dioxide in the Martian atmosphere, where the element makes up 96%, into breathable oxygen.
A bit of chemistry 101 is that carbon dioxide molecules are made up of one carbon atom and two oxygen atoms. These fragments are basically stuck together. But an instrument inside MOXIE, called the Solid Oxide Electrolyzer, can pick up the oxygen fragments inside those CO2 molecules that scientists are interested in. Once completed, all free-floating oxygen particles recombine into O2, also known as molecules with two oxygen atoms. , also known as the kind of oxygen we know and love.
I know it’s different, but I keep thinking of Pixar’s WALL-E doing this. So, as WALL-E would say: Ta-da!
Technicians from NASA’s Jet Propulsion Laboratory lower the Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE) instrument into the belly of the Perseverance rover.
NASA/JPL-Caltech
“This is the first demonstration of using resources on the surface of another planetary body and chemically transforming them into something that would be useful for a human mission,” Hoffman said. “It’s historic in that sense.”
Along the way, this process requires the use of very high heat, reaching temperatures of approximately 1,470 degrees Fahrenheit (800 degrees Celsius), which is fascinatingly what gives MOXIE its signature gold coating.
As with NASA’s pioneering James Webb Space Telescope, MOXIE must be shielded from infrared heat because it operates on heat itself. A gold coating does just that, and in fact, JWST’s mirrors are also gold-coated for the exact reason.
A wing of the James Webb Space Telescope’s main mirror opens into place during a final test of the mirror deployment system in May 2021. Check out this gold-plated beauty.
NASA
Next, the MOXIE team intends to demonstrate that MOXIE performs well under even more intense conditions, such as an upcoming run that will occur during the “highest density of the year,” Hecht said. “We’ll put everything as high as we dare, and let it run as long as we can.”