Steven Novella in Neurologica Blog:
One of the major challenges of space travel is that there are no ready-made resources there. Mars, for example, has no food, shelter, oxygen, fuel, or power. It likely has water, but it’s not certain how much and how accessible. So for now any human mission to Mars will have to bring all recourses from Earth. Getting stuff to Mars is massively expensive, and resupply can take 6-9 months, during optimal launch windows. Keeping humans alive on Mars for any length of time is therefore a very tenuous and expensive endeavor.
One obvious solution is what NASA calls “in-situ resource utilization,” – using stuff that is already there. The Perseverance rover on Mars contains an experiment called MOXIE (Mars Oxygen In-Situ Resource Utilization Experiment) that has taken the first step toward the goal of in-situ resource use. MOXIE was developed by engineers at MIT, it is a lunch-box sized experiment onboard the Perseverance that makes oxygen from the Martian atmosphere. It is essentially a proof-of-concept, and if it works may be the forerunner of far larger machines in the future.
More here.