Mars colonists could create a carbon dioxide plasma in order to supply oxygen to their settlement(s):
The atmosphere on Mars is 96 per cent carbon dioxide, says Vasco Guerra at the University of Lisbon in Portugal. This can be split to extract breathable oxygen and carbon monoxide, a fuel that could give us a "gas station on the Red Planet", he says. He and his team calculate that creating a carbon dioxide plasma — a mush of ions made by passing an electric current through a gas — could split carbon dioxide from oxygen more easily on Mars than on Earth.
The lower atmospheric pressure on Mars would allow us to create plasmas without the vacuum pumps or compressors necessary on Earth. Also, the temperature of around -60°C is just right to let the plasma more easily break one of the chemical bonds that keeps carbon and oxygen tightly bound, while preventing the carbon dioxide from re-forming.
For now, this is largely theoretical, but they say such a system needing only 150 to 200 Watts for 4 hours each 25-hour Mars day could produce 8 to 16 kilograms of oxygen. "The International Space Station currently consumes oxygen in the range of 2 to 5 kilograms per day, so this would be enough to support a small settlement," says Guerra.
The case for in situ resource utilisation for oxygen production on Mars by nonequilibrium plasmas (open, DOI: 10.1088/1361-6595) (DX)
(Score: 0) by Anonymous Coward on Sunday October 29 2017, @03:02AM (1 child)
>"Plants need light" isn't entirely true
Are you thinking of fungi as plants? Photosynthesis needs light.
>and with modern bioengineering we could probably improve low-light growth
On Mars, sunlight is 44% as bright [colorado.edu] as on Earth. Plants that are well-adapted to that amount of light already exist, because we have forests on Earth.
(Score: 2) by t-3 on Sunday October 29 2017, @04:26AM
Not all plants require photosynthesis. Never did that "grow $X in a dark closet" grade-school science experiment? With appropriate nutrition etc, a lot of stuff can be grown without sunlight.