Perseverance rover to create oxygen on the surface of Mars
When NASA’s Perseverance rover touches down in Jezero Crater on February 18, 2021, it will carry with it an experiment that will attempt to transform atmospheric carbon dioxide into precious oxygen. Future crewed missions to the Red Planet could use large amounts of converted oxygen to create fuel with which to launch return rockets from the surface of Mars.
Launching materials into space is a phenomenally difficult and expensive endeavor, with a price tag of roughly US$10,000 per pound of cargo launched in to orbit. To save on costs and make the ambitious goal of exploring Mars more realistic, NASA and its partners are exploring ways that future astronauts can utilize resources native to the Red Planet to survive and, eventually, return to Earth.
One of the most vital resources that astronauts will need to explore Mars is oxygen. This precious gas is needed for a range of purposes. Most obviously the human crew will need fresh oxygen to breathe, but it is also a key ingredient needed to synthesize the rocket fuel needed to power a rocket on the return trip to Earth.
NASA’s Perseverance rover is set to test the feasibility of producing oxygen on the Red Planet after descending to the Martian surface, with the use of its Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE) instrument.
The Martian atmosphere is incredibly thin relative to Earth’s atmospheric shield, and is comprised of 95 percent carbon dioxide.
The toaster-sized instrument is designed to suck the plentiful supply of CO2 from the atmosphere using an air pump, and electrochemically separate the greenhouse gas into its constituent parts, with each molecule yielding two atoms of oxygen and one of carbon. The results of the experiment would then be analyzed to gauge the purity and amount of oxygen produced.
"MOXIE is designed to make about six to 10 grams of oxygen per hour – just about enough for a small dog to breathe," said Asad Aboobaker, a MOXIE systems engineer at NASA's Jet Propulsion Laboratory in California. "A full-scale system geared to make (propellant for the flight home) would need to scale up oxygen production by about 200 times what MOXIE will create."
This process runs at a high temperature – 1,470 °F (800 °C) to be precise – requiring the instrument to be constructed from heat-resistant materials including 3D-printed alloy elements that help distribute the excess heat. The box-shaped experiment is also coated in gold to protect the rest of the rover from the infrared radiation being generated during the oxygen creation process.
Perseverance’s science team is expected to run MOXIE 10 times over the course of a two-year period in order to test how efficiently the experiment is able to harvest oxygen from the atmosphere in varying Martian seasons.
Scientists are currently working to create a full-sized MOXIE oxygen extractor, which is set to be far larger than the Perseverance experiment, and could weigh around 2,200 lb (1,000 kg).