NASA sent the Perseverance rover to Mars with some bonus technology – a device that can turn carbon dioxide into oxygen, just like trees do on Earth.
The device, called the Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE), pulled carbon dioxide from Mars’ atmosphere to produce its first oxygen on Tuesday. It’s a small amount – 5.4 grams, enough to keep an astronaut healthy for 10 minutes – but it’s proof that the technology is working on the red planet.
That’s good news for the prospect of sending human explorers to Mars. Oxygen takes up a lot of space on a spacecraft, and it is very unlikely that astronauts will be able to take enough to Mars. So they will have to produce their own oxygen from the atmosphere of Mars, both to breathe and to fuel rockets to return to Earth.
Artist’s concept of astronauts and human habitats on Mars.
JPL / NASA
“This is a critical first step in converting carbon dioxide into oxygen on Mars,” Jim Reuter, associate administrator of NASA’s Space Technology Mission Directorate, said in a press release on Wednesday.
“MOXIE has more work to do, but the results of this technology demonstration are very promising as we reach our goal of one day seeing humans on Mars,” he added. “Oxygen is not just what we breathe. Rocket propellant depends on oxygen, and future explorers will depend on the production of propellant gas on Mars to make the journey home.”
The gold box containing the experiment is about the size of a car battery – just 1% the size of the device scientists actually hope to send to Mars.
MOXIE descendants could eventually produce enough oxygen – about 25 tons – to launch four astronauts from the surface of Mars. Producing that oxygen on site would save a lot of space, weight, fuel, and money for the maiden voyage to Mars.
How MOXIE extracts oxygen from the air
Perseverance’s ‘selfies’ on Mars.
NASA / JPL-Caltech
This isn’t the only technology first from this week’s Perseverance mission. Another experiment that took it to Mars, the Ingenuity helicopter, made history when it first flew above the surface of Mars on Monday.
“Tech demonstrations are really a very critical element of our portfolio,” Thomas Zurbuchen, NASA’s Associate Administrator, told Insider before Ingenuity’s flight. “They actually enable new tools in our toolbox.”
Perseverance took a ‘selfie’ with the Ingenuity helicopter on April 6, 2021.
NASA / JPL-Caltech / MSSS / Sean Doran
NASA expects MOXIE to extract oxygen from the atmosphere of Mars at least nine more times over the next two years. This first attempt was to make sure the experiment worked. Future runs will test MOXIE’s capabilities at different times of the day and throughout the seasons of Mars. The device is designed to generate up to 10 grams of oxygen per hour.
In any case, MOXIE will not run out of fuel for these tests. The atmosphere of Mars is 96% carbon dioxide. The device uses heat and electrical currents to split those CO2 molecules into oxygen (O) and carbon monoxide (CO). Oxygen atoms don’t like to be alone for long, so they quickly combine to form O2 molecules – the oxygen we breathe.
The final product should be nearly pure molecular oxygen: approximately 99.6% O2.
MOXIE then returns both the oxygen and carbon monoxide to the planet’s atmosphere. However, future scaled-up devices would store the oxygen in tanks for later use.
Workers install MOXIE in the Perseverance Mars rover chassis at NASA’s Jet Propulsion Laboratory in Pasadena, California on March 20, 2019.
NASA / JPL-Caltech
Converting carbon dioxide into oxygen isn’t the only way future astronauts can make a living off the land of Mars. Scientists and engineers have also proposed using rocks on site to build structures, or even excavate Mars or moon ice to make drinking water or rocket fuel.
Whichever method it chooses, NASA will have to become resourceful in expanding the human presence in deep space. MOXIE’s success puts another technology in its toolbox.