Scientists say that plants can grow on the moon, but they might not be as plentiful as once hoped.
As part of an ongoing effort to study samples from space, Apollo astronauts previously collected samples of lunar surface material, known as regolith, and brought them back to Earth.
NASA says that now, 50 years later, three of those samples were used to grow plants for the first time successfully.
Researchers at the University of Florida grew Arabidopsis thaliana in the nutrient-poor lunar regolith. Arabidopsis thaliana is a well-researched small flowing plant native to Eurasia and Africa. They are a relative of mustard greens and other cruciferous vegetables.
“This research is critical to NASA’s long-term human exploration goals as we’ll need to use resources found on the Moon and Mars to develop food sources for future astronauts living and operating in deep space,” said NASA Administrator Bill Nelson. “This fundamental plant growth research is also a key example of how NASA is working to unlock agricultural innovations that could help us understand how plants might overcome stressful conditions in food-scarce areas here on Earth.”
When starting the research, University of Florida scientists worked to find answers to two crucial questions.
“We first asked the question of whether plants can grow in regolith. And second, how might that one day help humans have an extended stay on the moon,” said Robert Ferl, a professor in the Horticultural Sciences department at the University of Florida.
Planting on the moon
The answer to the University of Florida scientists’ first question was a resounding ‘yes.’ Plants can grow in the moon’s soil.
NASA says that while plants did grow, they were not as robust as plants grown in Earth soil or even as those in the control group grown in a lunar simulant made from volcanic ash.
“To explore further and to learn about the solar system we live in, we need to take advantage of what’s on the moon, so we don’t have to take all of it with us,” said Jacob Bleacher, the Chief Exploration Scientist supporting NASA’s Artemis program at NASA Headquarters in Washington.
NASA hopes that when it sends robots to the moon’s south pole, they will find water that future astronauts can use.
“What’s more, growing plants is the kind of thing we’ll study when we go. So, these studies on the ground lay the path to expand that research by the next humans on the moon,” Bleacher said.
From seeds to plants
The team of scientists used samples from Apollo 11, 12 and 17.
A gram of the regolith was allotted for each plant, and the team added water and seeds to the samples. The terrarium boxes were then placed in a clean room, and researchers added nutrient solution daily.
“After two days, they started to sprout!” said Anna-Lisa Paul, a professor in Horticultural Sciences at the University of Florida. “Everything sprouted. I can’t tell you how astonished we were! Every plant – whether in a lunar sample or in a control – looked the same up until about day six.”
Scientists say that after day six, it was clear that the plants were not as robust as the control group plants growing in volcanic ash, and the plants were growing differently depending on which type of sample.
The plants were said to have grown more slowly and had stunted roots. Some even had stunted leaves and sported reddish pigmentation.
The plants were harvested after 20 days, just before the plants started to flower.
After researchers studied the proteins within the plants, they found patterns of genes were under stress and reacted the way they’d seen when grown in harsh environments.
Ultimately, the plants reacted differently depending on the sample and which moon area was used. Researchers said that the plants grown in Apollo 11 samples were not as robust as the other two sets.
Sowing seeds for future research
While the plants weren’t as strong as they hoped, the research will help to study the lunar regolith further and help them understand where to find the best soil to plant on the moon.
“Not only is it pleasing for us to have plants around us, especially as we venture to new destinations in space, but they could provide supplemental nutrition to our diets and enable future human exploration,” said Sharmila Bhattacharya, program scientist with NASA’s Biological and Physical Sciences (BPS) Division. “Plants are what enable us to be explorers.”
Pieces of the moon will help this mission identify the growth of plants and future other future missions.