NASA has sent the Perseverance rover to Mars with a bonus technology: a device that can turn carbon dioxide into oxygen, just like trees on Earth.
The device, called the Mars Resource Use Experiment (MOXIE), extracted carbon dioxide from the Martian 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 works on the red planet.
This is good news for the prospect of sending human explorers to Mars. Oxygen takes up a lot of space on a spacecraft and astronauts are very unlikely to be able to bring enough with them to Mars. So they will have to produce their own oxygen from the Martian atmosphere, both for respiration and for rocket power to return to Earth.
The 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 director of NASA’s Space Technology Mission Directorate, said in a news release Wednesday.
“MOXIE has more work to do, but the results of this technology demonstration are full of promise as we move toward our goal of one day seeing people on Mars,” he added. “Oxygen is not just what we breathe. The rocket propellant depends on oxygen, and future explorers will depend on the production of propulsion on Mars to make the journey home.”
The gold box containing the experiment is about the size of a car battery – only 1% of the size of the device that scientists hope to send to Mars.
MOXIE’s descendants could eventually produce enough oxygen – about 25 metric tons – to launch four astronauts from the Martian surface. On-site oxygen production would save a lot of space, weight, fuel and money for the initial trip to Mars.
How MOXIE removes oxygen from the air
The “selfies” of perseverance on Mars.
NASA / JPL-Caltech
This is not the only technology premiere of the Perseverance mission this week. Another experiment he carried on Mars, the Ingenuity helicopter, made history when it first flew over the Martian surface on Monday.
“Technical demonstrations are a very important part of our portfolio,” Thomas Zurbuchen, NASA’s associate administrator, told Insider before Ingenuity’s flight. “They basically allow 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 Martian atmosphere at least nine times over the next two years. This first test was designed to ensure that the experiment worked. Future runs will test MOXIE skills 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.
At the very least, MOXIE will not run out of fuel for these tests. Mars’ atmosphere is 96% carbon dioxide. The device uses heat and electricity to divide those molecules of CO2 into oxygen (O) and carbon monoxide (CO). Oxygen atoms don’t like to be alone for long, so they combine quickly into O2 molecules – the oxygen we breathe.
The final product should be almost pure molecular oxygen: about 99.6% O2.
MOXIE then releases both oxygen and carbon monoxide back into the planet’s atmosphere. However, future extended devices would store oxygen in tanks for later use.
Workers install MOXIE in the chassis of the Perseverance Mars rover at NASA’s Jet Propulsion Laboratory in Pasadena, California, on March 20, 2019.
NASA / JPL-Caltech
Converting carbon dioxide to oxygen is not the only way future astronauts could live on Martian earth. Scientists and engineers have also proposed using the rocks on site to build structures or even dig up Martian or lunar ice to produce drinking water or rocket fuel.
Whatever method you choose, NASA will need to obtain resources to expand its human presence into deep space. The success of MOXIE puts another technology in its toolbox.