Earthworms Born in NASA's Mars Soil for First Time Raises Prospect of Farming on the Red Planet

The planet Mars, 25 February 2007. European Space Agency

Worms have been born in a Mars soil simulant for the first time, bringing the prospect of farming on the Red Planet a step closer to reality. As earthworms are fundamental to healthy soil on Earth, their reproductive success could be integral to agricultural sustainability on Mars—good news for Elon Musk, who recently announced a plan to colonize Mars by 2022.

Wieger Wamelink, a biologist based at Wageningen University and Research Center in the Netherlands, observed the critters in a soil sample being used to grow arugula. This soil, developed by NASA, mimics the kind of sustainable closed agricultural ecosystem necessary to support human life on Mars.

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One of the young earthworms discovered in the Mars-like soil Wageningen University & Research

On Mars, soil samples will be fertilized using human waste. In this experiment, pig slurry was used for practical and safety reasons. Wamelink added the manure to the soil with adult earthworms in order to improve soil quality.

"For a sustainable agricultural ecosystem on Mars, indoors and under earth like air and pressure, worms are essential. Nutrients in the dead plants must be brought back to the soil and worms help to do so," he tells Newsweek. "That the worms would thrive was not obvious, since there are heavy metals present in the soil and the sand grains can quite sharp."

Worms dig through soil, eating and excreting dead organic matter. Their burrowing habits can change soil structure, improving the watering of plants. "This is an important part of the argricultural ecosystem we want to build on Mars that works," Wamelink says.

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Some of the plants grown in Mars-like soil. The front two pots are growing aragula. Wieger Wamelink

The soil samples used in the experiment, Wamelink cautions, are not completely identical to Martian soil. A "major drawback" of the research, he explains, is the absence of perchlorate—a toxic chemical compound found on Mars. In addition, the lower gravity found on Mars cannot be replicated in laboratory conditions.

"We will continue with the worms—providing funding—to upscale and to keep them for longer periods to see if they can continue to do their job—digging their burrows, chewing organic matter and mixing it with the soil," Wamelink says.

This experiment is part of the crowdfunded Food for Mars and Moon project, which has been attempting to cultivate crops in Mars-like and moon-like soil since 2013. Successfully harvesting crops for the first time in 2015, the team now needs to answer the question: is this food safe to eat?