It’s a small pot of soil, a giant leap for the knowledge of space agriculture by man: scientists have for the first time grown plants in lunar soil brought back by astronauts as part of the program Apollo.
The groundbreaking experiment, detailed in the journal Communications Biology on Thursday, gave researchers hope that it may one day be possible to grow plants directly on the Moon.
This would save future space missions a lot of hassle and expense, facilitating longer and more distant journeys.
However, according to the study authors from the University of Florida, there is still much to study on the subject, and they intend to leave no stone unturned.
“This research is critical to NASA’s long-term human exploration goals,” said Bill Nelson, director of the US space agency. “We will need to use resources found on the Moon and Mars to develop food sources for future astronauts living and operating in deep space.”
For their experiment, the researchers used only 12 grams (a few teaspoons) of lunar soil collected from various locations on the Moon during the Apollo 11, 12 and 17 missions.
In tiny pots the size of a thimble, they placed about a gram of soil (called “regolith”) and added water, then the seeds. They also fed the plants a nutrient solution every day.
The researchers chose to plant Arabidopsis thaliana, a relative of mustard greens, because it grows easily and, importantly, has been studied extensively. Its genetic code and its responses to hostile environments – even in space – are well known.
As a control group, seeds were also planted in Earth’s soil as well as samples mimicking lunar and Martian soil.
Result: after two days, everything germinated, including the lunar samples.
“Each plant – whether in a lunar sample or in a control – looked the same until about the sixth day,” Anna-Lisa Paul, lead author of the paper, said in a statement.
But after that, differences began to appear: the plants in the lunar samples grew more slowly and had stunted roots.
After 20 days, scientists harvested all the plants and conducted DNA studies.
Their analysis showed that the lunar plants reacted similarly to those grown in harsh environments, such as excessively salty soils or heavy metals.
In the future, scientists want to understand how this environment could be made more hospitable.
NASA is preparing to return to the Moon as part of the Artemis program, with a long-term goal of establishing a sustainable human presence on its surface.