NASA’s Perseverance rover has been marking milestones on Mars since landing on the Red Planet in February. Its latest historic accomplishment is the first creation of oxygen from carbon dioxide in the thin Mars atmosphere. Mission time is measured in sols, or Martian days. Oxygen production was achieved early in the evening of April 20, or early morning on Sol 60 in Jezero Crater.
MOXIE (Mars Oxygen In-situ Resource Utilization Experiment), a small, gold box-shaped instrument on the rover, successfully demonstrated a solid oxide electrolysis technology for converting the Martian atmosphere to oxygen. The atmosphere on Mars is about 95% carbon dioxide.
MOXIE’s first oxygen run produced 5.4 grams of oxygen in an hour. The power supply limits potential production to 12 g/hr — about the same amount that a large tree would produce.
For both rockets and astronauts, oxygen is crucial, says MOXIE’s principal investigator, Michael Hecht of MIT Haystack Observatory. “To burn its fuel, a rocket must have many times more oxygen by weight. To get four astronauts off the Martian surface on a future mission would require 15,000 pounds (7 metric tons) of rocket fuel and 55,000 pounds (25 metric tons) of oxygen.” In contrast, Hecht says, “The astronauts who spend a year on the surface will maybe use one metric ton between them to breathe.”
