For the first time in history, scientists have successfully grown plants in lunar soil, which is a major breakthrough in the field of space exploration. The ability to grow plants in space is crucial for future human colonization of the moon and Mars, and it could also help reduce the amount of food that needs to be transported from Earth to space.
The Importance of Growing Food in Space for Human Colonization
NASA has plans to send astronauts to the moon again in 2025, and by 2028, they hope to have a sustainable lunar presence. If humans can grow food on the moon, it will significantly reduce the need for shipping large amounts of food from Earth, which is expensive and logistically challenging. Moreover, learning how to grow food in lunar soil could potentially help us do the same on Mars when it’s time to send astronauts there.
The Challenge of Growing Plants in Lunar Soil
The challenge of growing plants in lunar soil is that it’s very different from terrestrial soil. It doesn’t contain any organic matter, and it’s filled with sharp meteorite fragments and exposed to tons of cosmic radiation. Even though NASA astronauts brought back samples of lunar soil during the Apollo missions, no one had ever attempted to grow anything in it before now.
Fifteen years ago, University of Florida researchers Rob Ferl and Anna-Lisa Paul submitted their first of several requests to NASA for lunar soil samples. They hoped to receive 4 grams from one Apollo mission, but 18 months ago, NASA sent them 12 grams total from three missions. This was far more soil than they were expecting, but it still only amounted to a few teaspoons of dirt. Therefore, the scientists had to be precious with it, placing about a gram’s worth in each thimble-sized well they were using as a “pot.” They then added a liquid nutrient solution and a few thale cress seeds to each well.
Thale cress was chosen because it’s well studied, and its genetic code has been fully mapped, meaning the researchers would be able to study the effect of the lunar soil on the plant’s gene expression. After planting seeds in simulated lunar and Martian soils, as well as terrestrial soils, to serve as controls for their experiment, the scientists waited to see what would happen. After two days, they were amazed that every single seed germinated.
However, on day six, the researchers began to notice that the lunar soil plants weren’t as robust as the controls. Their growth started to slow down, some of their roots and leaves became stunted, and a few developed a reddish pigmentation. On day 20, the researchers harvested the plants to study their genetic expression.
“At the genetic level, the plants were pulling out the tools typically used to cope with stressors, such as salt and metals or oxidative stress, so we can infer that the plants perceive the lunar soil environment as stressful,” Paul said.
The fact that the plants were able to germinate and grow in lunar soil is a significant achievement, but there’s still a lot of work to be done to figure out how to help them thrive in it. “Ultimately, we would like to use the gene expression data to help address how we can ameliorate the stress responses to the level where plants — particularly crops — are able to grow in lunar soil with very little impact to their health,” Paul said.
In conclusion, the successful growth of plants in lunar soil is a significant achievement that paves the way for future human colonization of the moon and Mars. If humans can grow food in space, it will reduce the need for costly and logistically challenging food shipments from Earth. Moreover, it will provide a sustainable food source for astronauts and potentially lead to the creation of a self-sufficient ecosystem on other planets. The next step is to figure out how to help plants thrive in lunar soil, and scientists are already working on it.