MOXIE: Innovative tech extracting Oxygen from Mars’s Atmosphere

The innovative technology known as MOXIE, short for Mars Oxygen In-Situ Resource Utilization Experiment, has successfully completed its scientific mission aboard NASA’s Perseverance rover. The device extracted oxygen from the Martian atmosphere 16 times, and each successful demonstration permitted the storage of valuable data for future Mars missions.

Moreover, thanks to these experiments, engineers can refine the techniques necessary for larger-scale oxygen production given that the Martian atmosphere is composed mainly of carbon dioxide and it could be really challenging to provide enough oxygen for future astronauts and inhabitants.

The first astronauts on Mars will need to generate oxygen to breathe and potentially rocket propellant to return to Earth.

An experimental device has generated oxygen for the 16th and final time aboard @NASAPersevere. Learn more about MOXIE: https://t.co/rcBQA6pdny pic.twitter.com/ZUrAHMQ2fe

— NASA Artemis (@NASAArtemis) September 10, 2023

Oxygen is essential both for creating breathable air for astronauts and as propellant for space rockets. The ability to process and reuse the resources funded in the mission location will allow a reduction of the mass of the load of the rocket and therefore simplify the expedition, making them less expensive and more efficient.

The device has been designed and built by engineers at the Massachusetts Institute of Technology (MIT). According to a NASA press release, it has produced 122 grams of oxygen, the equivalent of 10 hours of breathable air for a small-sized dog. To be specific, it has managed to produce up to 12 grams of oxygen per hour with a purity of 98%, surpassing NASA’s original expectations.

“Developing technologies that let us use resources on the Moon and Mars is critical to build a long-term lunar presence, create a robust lunar economy, and allow us to support an initial human exploration campaign to Mars”

— Pam Melroy, NASA Deputy Administrator

Moxie’s Mission

The most recent analysis took place on August 7th of this year, during which 9.8 grams of oxygen were produced. The engineers chose to operate MOXIE in various environmental conditions, adapting the device both to fluctuations of pressure present in the Martian atmosphere and to movements as the NASA Perseverance rover moved across the surface.

MOXIE operates through a process called “solid oxide electrolysis”:

1. CO2 Collection: extraction of CO2 from the surrounding Martian atmosphere (mainly composed of CO2, up to 95%);
2. Transformation in Solid Oxide Electrolysis: The extracted CO2 is then directed into a high-temperature solid oxide electrolysis stack made of ceramic materials capable of withstanding extreme conditions;
3. Separation of Oxygen and Carbon Monoxide: Inside the stack, CO2 molecules are decomposed under high temperature, separating into oxygen (O2) and carbon monoxide (CO);
4. Purification and Storage: the oxygen generated through this process is then purified and stored in a dedicated tank, ready for future use;
5. Release of Carbon Monoxide: the carbon monoxide produced as a byproduct is released into the Martian atmosphere.

Collected data

For instance, in the following tab, it is possible to read and understand better the results obtained. Four oxygen-producing cycles successfully completed by MOXIE in 2021 are reported:

Indeed, a significant objective of MOXIE is to demonstrate its practical functionality not only during Martian daytimes but also during nights, across all Martian seasons. This demonstrates its resilience in adapting to fluctuations in atmospheric pressure and temperature.

All previous research has been published in the scientific paper named “Mars Oxygen ISRU Experiment (MOXIE)—Preparing for human Mars exploration”.

The future development does not involve constructing MOXIE 2.0. Instead, the next step would be to develop a full-scale system equipped with an oxygen generator and a new device in order to liquefy and store that oxygen.