It still sounds like science fiction in the purest style The Martian, but today we are a little closer to growing plants on the Moon. A group of researchers from University of Florida (UFL) has succeeded for the first time in growing vegetables planted in lunar regolith —small soil samples from our satellite donated by the POT—, which has helped them to clarify how they respond and develop in a field “radically different” to that of Earth.
To prove it, researchers have had to use their imagination and, above all, economy of resources. After requesting samples on three different occasions over eleven years, NASA gave them 12 grams of lunar regolith collected decades ago, during the Apollo 11, 12 and 17 missions. It is little compared to the total reserves of the US agency, but —notes Engadget— exceeds the four grams that the researchers had initially requested.
With just a couple of tablespoons of lunar soil, the Florida team had to apply thoroughly. Researchers Rob Ferl and Anna-Lisa Paul used small, thimble-sized test tubes and materials commonly used for cell culture. In each of these tiny “pots” they added a gram of regolith, which they then watered with a nutrient solution. When the composition was ready and moistened, they planted several seeds of Arabidopsis.
With an eye on Artemis
Why Arabidopsis thalianacommonly known as Thale cress, and not any other? Basically because of how well we know her. “The Arabidopsis widely used in science because its genetic code has been completely mapped. Its cultivation in lunar soil has allowed researchers to better understand how it affects plants down to the level of genetic expression”, abound from the university, which has made a video detailing the entire process.
To get a bigger picture of how lunar soil affects plants, the researchers planted seeds in other soil samples: JSC-1A, a terrestrial composition that mimics the lunar soil, a simulation of Martian terrain, and a selection drawn from extreme environments on our planet. The result: the plants did not grow equally in all the test tubes. Moreover, the results vary from one lunar sample to another, depending on the area in which the regolith was taken.
Some of the plants grown on lunar soil were smaller or grew more slowly. “At the genetic level, they were bringing out the tools that are normally used to deal with stressorssuch as salt and metals or oxidative stress, so we can infer that plants perceive the lunar soil environment as stressful”, Paul concludes.
The samples with the most signs of stress were those that had developed on the ground of the satellite most exposed to the cosmic wind. Another question now being asked is what the reverse reaction is: to what extent can plant cultivation change the Moon’s terrain?
Paul and Ferl’s experiment is not a simple academic exercise to understand the response of plants to lunar soil. Its objective –recognizes the UF itself— is eminently practical. The plants have already helped us to learn more about lunar samples at the beginning of lunar exploration, when they were spread over the regolith to study the possible existence of pathogens.
“It is a first step to one day be able to grow plants to obtain food and oxygen on the Moon or during space missions,” he details. Ferl also recalls that the conclusions come in an interesting context: when NASA and its partners have Artemis on the table, the ambitious space program that aspires to take humans to the Moon for the first time in decades.
“Artemis will require a better understanding of how to grow in space”, he points out. Thanks to his work, perhaps we are a little closer to realizing —the selenite version— the adventures of The Martian. Or even to be able to prepare a salad with sprouts of lunar canons.
Pictures | University of Florida