Matt Damon grew potatoes in “The Martian,” but researchers are now exploring how moss could help turn barren space dust into fertile soil. A species called Physcomitrella patens, or spreading earthmoss, has shown remarkable resilience. It can survive for at least nine months on the outside of the International Space Station (ISS) and still reproduce once back on Earth.
Although this moss isn’t edible, it plays a crucial role in possible future space explorations. Dr. Tomomichi Fujita from Hokkaido University led a study that indicates moss could help create sustainable life-support systems in space. “Moss can aid in generating oxygen, controlling humidity, and even forming soil,” he notes.
Mosses have long fascinated researchers for their ability to endure extreme conditions. For example, the desert moss Syntrichia caninervis thrives under simulated Mars-like scenarios here on Earth. In a recent study published in iScience, Fujita’s team tested three moss structures in a simulated space environment. They discovered that spores encased in a structure called a sporangium were especially resilient. These spores survived high levels of UV radiation and other harsh conditions.
The team sent these encased spores to the ISS aboard the Cygnus NG-17 spacecraft. Attached outside the ISS for nine months, the spores returned to Earth displaying impressive germination rates—86% for those exposed to space conditions, compared to 97% for Earth-bound spores. However, some signs of chlorophyll degradation were noted in samples from space.
“If these spores can withstand long journeys in space and revive after rehydration, they might help establish ecosystems beyond Earth,” Fujita explains. But he also points out the study focused solely on survival in space; how moss would grow in different conditions remains uncertain.
Dr. Agata Zupanska from the Seti Institute, who wasn’t part of the research, cautions that while the findings are significant, they already knew dormant spores are tougher than hydrated forms. Similar experiments have been conducted on other seeds aboard the ISS.
She emphasizes that true deep space conditions, such as those on Mars or the Moon, are much more complex than what the ISS offers. “The real value of space plants comes from their ability to grow and thrive outside of Earth,” Zupanska says. While the resilience of spores is a promising start, more research is needed to understand how these plants can adapt to survive and flourish in extraterrestrial environments.
In short, moss could play a vital role in future space exploration, potentially helping us create the first green patches on other planets. The challenges ahead are significant, but the journey is just beginning.
