Plants can grow in lunar regolith, but they don’t welcome it

NASA returns astronauts to the Moon via the end of this decadeand hopes to send humans to Mars one day in the 2030s. Growing food in space using in situ resources is vital if astronauts are to survive both the Moon and Mars in the long term. Growing plants in space using Earth’s soil is nothing new, as this research is currently underway on board the International Space Station (ISS). But recent research on Earth has taken crucial steps towards being able to grow food in space using extraterrestrial material we took from the moon more than 50 years ago.

In a recent study Posted in Communications Biology, researchers have taken a remarkable first step in helping future astronauts on the Moon grow their own food using lunar regolith instead of Earth soil. This is an extraordinary discovery because it could help future astronauts on the Moon and Mars grow their own food using in situ resources instead of relying on resupplies from Earth to help them survive. What makes this research even more amazing is that it was carried out using lunar regolith that was returned from the Moon over 50 years ago by samples from Apollo 11, 12 and 17. .

“This research is critical to NASA’s long-term human exploration goals, as 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. “said NASA Administrator Bill Nelson. “This fundamental research on plant growth 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. “

Earth’s soil is rich in vital nutrients ideal for plant growth, including minerals (45%), water (25%), air (25%) and organic matter (5%). For Lunar regolith99% of the mass consists of water (41-45%), silicon (Si), aluminum (Al), calcium (Ca), iron (Fe), magnesium (Mg) and titanium (Ti), and almost all of the remaining 1% is made up of manganese (Mn), sodium (Na), potassium (K) and phosphorus (P).

“Here we are, 50 years later, completing experiments that began in Apollo Laboratories,” said Robert Ferl, a professor in the Department of Horticultural Sciences at the University of Florida at Gainesville and co-author of the study. “We first asked ourselves whether the plants could grow in the regolith. And two, how could it ever help humans have an extended stay on the Moon.

For the study, the team developed the well-studied Arabidopsis thaliana, which is native to Eurasia and Africa, and is a relative of mustard greens and other cruciferous vegetables (cabbage family) such as broccoli, cauliflower, and Brussels sprouts. Due to its small size and ease of growth, it is one of the most studied plants in the world. Because of this, scientists already know what its genes look like, how it behaves in different circumstances, and even how it grow in space.

Using samples from Apollo 11, 12 and 17, the research team only used one gram of regolith for each plant. They then added water and seeds to the samples. They then placed the trays in terrarium boxes in a clean room, and nutrient solution was added daily. After only a few days, the results looked promising.

“After two days, they started sprouting!” said Anna-Lisa Paul, professor of horticultural science at the University of Florida and first author of the paper. “Everything sprouted. I can’t tell you how surprised we were! Every plant – whether in a lunar sample or in a control – looked the same until about the sixth day. It was only after the sixth day that the research team realized that the plants growing in the regolith were not as hardy as the plants in the control group growing in the volcanic ash. To make matters worse, the regolith plants grew differently depending on the type of sample they were in. They grew more slowly and had stunted roots; moreover, some had stunted leaves and sported a reddish pigmentation.

After 20 days, just before the plants started to flower, the team harvested the plants, ground them up and studied the RNA. This showed that the plants were indeed stressed and reacted as the researchers saw Arabidopsis respond to growth in other harsh environments, such as when the soil contains too much salt or heavy metals. As noted, the regolith used in this study came from three Apollo samples, all collected from three different sites on the Moon. It was revealed that the plants grown in the Apollo 11 samples were not as hardy as the plants in the Apollo 12 and 17 samples.

Although the plants did not ultimately turn out as hoped, this research nonetheless opens the door to not only growing plants in habitats on the Moon, but it also opens the door to further study. This includes understanding the genes plants need to adapt to growing in regolith, evaluating how different Moon materials are more conducive to plant growth than others, and study of lunar regolith to also help us better understand the regolith of Mars.

“Not only is it nice for us to have plants around us, especially as we venture to new destinations in space, but they could provide additional nutrition to our diets and enable future human exploration.” , said Sharmila Bhattacharya, a scientist with NASA’s Biological and NASA program. Division of Physical Sciences (BPS). “Plants are what allow us to be explorers.”

Lunar Sample Laboratory Facility

Although the samples used in this research are 50 years old, this research was made possible due to the Lunar Sample Laboratory Facility at the Johnson Space Center in Houston, TX. The purpose of this facility is to maintain lunar samples in pristine condition to enable current and future studies by scientists and educators around the world. Part of the facility is dedicated to the long-term storage of lunar samples for later study as research technology improves.

As always, keep doing science and keep looking up!

Press release: Nasa

Sources: Space.com, Nasa (1), Nasa (2), Communications Biology, united states department of agriculture, Washington University in St. Louis, The Arabidopsis Information Resource, Astrobiology, Nasa (3)