Oxygen is one of the biggest hurdles to human space exploration. Earth is the only place we know of that has the vital gas in breathable quantities, and taking it with us is expensive and unsustainable. On the International Space Station, the crew breathes easy thanks to electrolysis – where water is zapped to split it into its constituent hydrogen and oxygen gases – along with a pressurized storage tank for backup. There's talk of terraforming Mars to be more Earth-like, but that's a huge undertaking that isn't remotely possible with today's technology.

So the researchers on the new study set out to find another way to produce oxygen. They ended up creating a reactor that, in a sense, sounds very simple – take CO2, then strip out the C. The team found that if you shoot carbon dioxide at an inert surface like gold foil, the molecule can be split to form molecular oxygen and atomic carbon.