A 2025 study published in iScience revealed that moss spores can survive the harsh conditions of outer space. Researchers from Hokkaido University, in Japan, conducted lab testing on juvenile moss, moss stem cells and moss spores encased in sporophyte structures, exposing them to simulated space conditions. The sporophytes were 1,000 times more tolerant of ultraviolet radiation than the stem cells. They even managed to endure temperatures as cold as -320° F for more than a week and as hot as 130° F for an entire month.

To validate these lab findings, hundreds of sporophytes spent 283 days on a platform attached to the International Space Station before returning to Earth. More than 80 percent of the spores survived the journey, and of those, 89 percent were subsequently able to germinate.

Mathematical models indicate that spores could potentially survive up to 15 years in space. Researchers believe the sporophytes’ tough outer coating shields the spores from radiation and extreme temperatures. This research could help us understand life’s resilience on Earth and pave the way for building ecosystems in extra-terrestrial environments.