The excellent news for proponents of space colonization is that scientists have shown you possibly can grow plants in Moon dirt. However the bad news for anyone envisioning a lushly verdant lunar astronaut salad bar is that plants grown in lunar regolith don’t grow thoroughly and are generally stressed by the experience.
In a recent study published Thursday within the journal Communications Biology, researchers on the University of Florida grew plants in lunar regolith from Nasa’s Apollo missions for the primary time, comparing their growth to that of plants seeded in terrestrial volcanic ash.
The lackluster performance of the plants grown within the Apollo samples presents a challenge for proponents of in “situ resources utilization,” the term for astronauts creating their water, oxygen, fuel, or on this case, food, from resources found on an extraplanetary body fairly than pack them from home.
The researchers seeded Arabidopsis thaliana, a small flowering plant more commonly often called thale cress, either in samples of lunar regolith brought back to Earth by the Apollo 11, 12, and 17 missions, or in a volcanic ash-based control soil designed to mimic lunar regolith. The plants seeded into the Moon samples grew slower, smaller, and showed more signs of stress comparable to pigmentation and the expression of stress-related genes, than those grown within the volcanic ash.
And while the plants grown in volcanic ash developed kind of uniformly, the plants grown within the Apollo 11 samples fared worse than the plants within the Apollo 12 and 17 samples, suggesting variability within the samples. The Apollo 11 sample, as an illustration, was exposed to solar and cosmic radiation the longest, and the researchers theorize the consequences of that long-term energetic bombardment could have left the lunar regolith particularly reactive to biology.
The study is the primary to aim growing plants in lunar regolith as the first growth medium, and the outcomes contrast with those of experiments conducted within the Nineteen Seventies.
Through the Apollo program, researchers crumbled lunar regolith, giving plants growing in terrestrial soil a veneer of Moon dust, and located the plants actually thrived in comparison with controls. The experiments were mainly focused on ensuring no unknown pathogens or toxins lurked within the Moon samples astronauts brought back, and researchers believed the extra nutrients were liable for the plants’ growth.
Seeds taken to the Moon by Apollo astronauts and returned to Earth were then planted, with many successfully growing into mature “Moon trees,” however the experiment addressed the viability of seeds taken to space, not seeds in soil from space.
More recently, in 2019, an experiment on China’s Chang’e 4 lunar lander successfully germinated seeds on the Moon for the primary time, but did so in a sealed container using Earthly soil
The present study’s takeaway is that growing crops on the Moon won’t be as easy as simply putting up a pressurized greenhouse and planting seeds. As with other experiments with in situ resource utilization, more research is required.
Space agencies like Nasa and the European Space Agency are currently researching many alternative technologies for utilizing resources present in space in order that astronauts wouldn’t have to pack all the pieces they need with them from Earth. Esa scientists are studying find out how to extract oxygen from molten lunar regolith, as an illustration, while an experimental device on Nasa’s Perseverance Mars rover is extracting oxygen from the Red Planet’s thin atmosphere.
Nasa plans to return to the Moon in 2025 as a part of the space agency’s Artemis program, which goals to make use of the Moon as a practice zone before a mission to Mars within the early 2040s. Astronauts spending weeks or months on the Moon may have ample opportunity to experiment with in situ resource utilization, including ways of modifying lunar regolith to be more friendly to plants.
And it could take quite a lot of experimentation, in keeping with the current study’s authors.
“Further characterization and optimization can be required before regolith will be considered a routine in situ resource, particularly in locations where the regolith is extremely mature,” they wrote within the paper.