Silly study.
Looking into the study, they used Earth temperatures and sunlight, air pressure and humidity. They did not simulate the radiation on Mars. The only thing "Martian" was the soil.
Actually, the study only says they used "Mars regolith simulant JSC 1A", and a quick Google says that this stimulant does *not* include any perchlorate. I am not sure how perchlorate affects plants, but it's clear that perchlorate is absorbed by plants. So if it's in the soil it's in your food, and perchlorate is dangerous to humans. It's 0.6% of Martian soil.
So this study is fun and all, but all it tells us is that if you built a radiation-proof dome or underground space and filled it with Earth air (composition, pressure, humidity) and provided Earth-like sunlight you could grow inedible food. Or edible food, if you have a magic wand that will remove perchlorate from the Martian regolith or from the food.
Interestingly, one of the methods used on Earth to remove perchlorate from soil is plants.
As for the Earth-like sunlight, you can create that with LEDs of course. But since Mars is twice as far from the Sun as Earth solar panels receive 1/4 as much solar energy. I'm assuming whatever we use to shield our veggies from the radiation also blocks the weak sunlight. The best solar panels today are about 22% efficient, but let's say by the time we go to Mars we get that up to 25% to keep the math easy. The best LEDs are just under 50% efficient. That means that for each square meter of plant growing space you will need 32 square meters of solar panels. That's ignoring the dust, length of day, etc.
Using Earth years, a square meter produces about five pounds of food per year (optimistically, depending on the crop.). Solar panels last 20-30 years. So you ship 32 square meters of solar panels to Mars to produce 150 lbs of food? Solar panels on the general market weigh 10-20kg per square meter, but let's say the special ones we send to Mars weigh 1/4 of the low end, 5 lbs/square meter. So now we're talking 160lbs of solar panels to produce 150 lbs of food. I'm assuming we can use waste heat to keep the crops warm, so we won't need additional solar panels for that.
And that ignores whatever is involved in building the space where we can create these conditions, the weight of the farmbots, etc.
So someone proposed this experiment and someone paid for it and someone got paid to write about it, but it tells us something close to nothing.
If we want to go to Mars with a substantial population for a substantial period, we need a few things:
Nuclear power – solar power on Mars is not worth much (though it's doing a fine job for some of the rovers).
Algae that doesn't have perchlorate uptake that will sustain human life and which grows in freezing temperatures.
Robots that will go first and dig the tunnels we'll have to live in.
A way to preserve human health indefinitely in a low gravity environment.
A way to allow humans to survive perchlorate – chelation, genetic engineering, medication, whatever.
Ultimately, the question I want to ask is: why Mars? What does being on the surface of Mars offer us that is not available in space?
paints piebald and skewbald horses.
