Remember that scene in The Martian where actor Matt Damon grows crops in a makeshift greenhouse on Mars so he can eat them? There are people on Earth making that a reality.
Since 2013, a Dutch researcher has successfully been cultivating crops and wild plant varieties in a soil that closely resembles that from the red planet and the moon. Now lab results have shown that four of his crops are safe for human consumption.
Wieger Wamelink, an ecologist at the Wageningen University in the Netherlands initially wanted to grow a garden in a computer simulation using the scientific data he had on Martian and moon soil. However, when he discovered that NASA sold "Mars soil"—soil that is found on Earth but shares similar chemical properties to Martian soil—Wamelink knew he had to try it out for real.
"Nobody could tell what would happen if you tried growing crops in this soil as NASA had made it to test habitats, rovers, and not for crop cultivation," explained Wamelink. "People couldn't even tell me what would happen if I added water to it."
Wamelink bought 50 kg of Martian soil and 50 kg of moon soil, each for around 500 euros, and set out growing his crops. His first experiment in 2013 was a test to see if plant germination was even possible using these extra-terrestrial-like soils. Wamelink grew each crop in a control, moon soil, and Mars soil pot. Over a course of 50 days, he witnessed everything from radishes to peas flower in the mars and moon soil pots, convincing him that the next step would be to see if these crops were edible.
"Last year, we were able to grow 10 different crops, but we didn't know if we could eat them; if it was safe. This year, we grew 10 different crops again, and we're now testing whether it's safe to eat them," said Wamelink.
Replica Martian soil has the same silicium oxide base as regular soil on Earth, although it contains heavier metals such as lead, cadmium, and arsenic that are toxic to humans. Plants are resistant to such toxic metals and continue growing regardless. As this could pose problems to humans who consume the plants, Wamelink is currently analysing whether these harmful metals are absorbed by the plants.
Ultimately, the project is exploring how possible it will be to create a sustainable food source using the red planet's natural resources, once humans set up a colony there.
"You could fly in the food that you'd need, but that's costly and takes time. It would be much easier to just bring some seeds and grow some crops over there," said Wamelink. "Everything will be grown in a controlled environment, but it would be handy if you could use the soil that's available on Mars."