Humans a step closer to Mars after Nasa creates oxygen from its atmosphere

Mars - World Perspectives
Mars - World Perspectives

Humans have moved a step closer to settling on Mars after oxygen was created on the planet for the first time.

Nasa has successfully generated oxygen through its instrument named Moxie.

Mounted to the Mars Perseverance rover, the toaster-sized device works by splitting the carbon dioxide-rich atmosphere.

Any hopes to send humans to Mars in the next 20 years depend on the ability to make oxygen on the surface for the astronauts.

Moxie has been turned on seven times since February 2021 and ran at full tilt for an hour at a time, with each test done in different conditions, including various seasons, daytime and nighttime.

Nasa found that about 50 grams worth of oxygen was made during the seven cycles, which the builders of Moxie at MIT say is akin to the productivity of a small tree.

Moxie stands for Mars Oxygen In-Situ Resource Utilisation Experiment and involves a high-quality air filter cleaning detritus from the atmosphere, and then compressing the wispy atmosphere - which is 95 per cent CO2 - to the same pressure of Earth’s air. It is also heated to 800°C before being transferred to a custom-built tool called SOXE.

SOXE - solid oxide electrolysis - passes electricity from an anode to a cathode to convert CO2 into carbon monoxide (CO) and oxygen.

Moxie twice ran an analysis of the oxygen it had created and found it to be pure as well as meeting the six grams of oxygen per hour target.

Scientists are trying to find ways to manufacture essential materials on different planets to save on having to transport them from Earth. Oxygen is perhaps the most important of them all as it is vital for both astronauts and the creation of rocket fuel.

Nasa hopes to have humans on the moon within 20 years and Elon Musk, the billionaire founder of SpaceX, hopes to have a permanent colony on our celestial neighbour.

But the air on Mars is fatal to humans and unable to support life, so reliably producing oxygen is essential to the success of future missions.

The reliability and consistency of Moxie’s oxygen production has proved the principle, and now engineers want to scale it to be able to make several tons of oxygen, like a robotic forest.

In future, a ramped-up version of Moxie may be sent to the Martian surface ahead of a crewed mission to make ample stores of the vital gas.

While it can be inhaled by astronauts, they will also need around 25 tons of oxygen to launch a rocket from the Martian surface to get home. Not only is making oxygen on Mars crucial to the survival of astronauts, it is utterly essential to bringing them back to Earth.

Instead of running in one-hour bursts, the technology would operate around the clock.

Drastically changing conditions

Prof Jeffrey Hoffman, Moxie deputy principal investigator from MIT’s Department of Aeronautics and Astronautics, called the new data, published in Science Advances, “historic”.

“This is the first demonstration of actually using resources on the surface of another planetary body, and transforming them chemically into something that would be useful for a human mission,” he added.

Running Moxie at various times of the Martian year and during different times of day was a key challenge to prove it can still make oxygen even under drastically changing conditions.

“The atmosphere of Mars is far more variable than Earth,” Prof Hoffman said.

“The density of the air can vary by a factor of two through the year, and the temperature can vary by 100 degrees. One objective is to show we can run in all seasons.”

Michael Hecht, the principal investigator of the Moxie mission at MIT’s Haystack Observatory, said the only time of day they have not run Moxie is dawn or dusk when the temperature is rapidly increasing or decreasing.

However, he said the team has “an ace up the sleeve” to cope with even these most challenging of conditions.

“Once we test that in the lab, we can reach that last milestone to show we can really run any time,” he said.