In the vast and challenging space environment characterized by vacuum, freezing temperatures, and high ultraviolet radiation, a unique type of moss has captured the interest of Japanese researchers. In a recent study released on Thursday, scientists dispatched a species of moss known as Physcomitrium patens to the International Space Station (ISS) for a nine-month exposure to the harsh conditions of space.
The researchers examined three developmental stages of the moss: protenemata (juvenile moss), brood cells (specialized stem cells), and sporophytes (reproductive structures containing spores). While not all stages survived the space conditions, the results were intriguing. The juvenile moss failed to withstand the intense ultraviolet radiation and temperature fluctuations. In contrast, the brood cells exhibited a better survival rate enduring freezing temperatures for 30 days, with 80% of the sporophytes managing to survive.
Lead researcher Tomomichi Fujita from Hokkaido University highlighted the significance of the study, noting that the moss could endure a nine-month space exposure without growth. Upon return to Earth, approximately 90% of the spores successfully germinated and thrived in a laboratory environment. Further analysis is required to determine if the spores underwent any changes during their space journey.
The study of plants in space has a rich history, especially focusing on their adaptability to extraterrestrial conditions. Cultivating plants in space stations is already a reality, with potential implications for future human colonization efforts on the moon and Mars. Plants not only provide essential nutrition but also contribute to mental well-being, as greenery and fresh produce can significantly impact astronauts’ psychological health.
Researcher Catherine Neish emphasized the critical role of plants in space missions, highlighting their importance for sustenance and mental health support for astronauts. Neish participated in an experiment in 2024 involving the growth of plants in lunar and Martian regolith, with promising results in lunar soil cultivation.
Fujita’s choice of Physcomitrium patens for the study stemmed from its resilience. The researchers speculate that the moss’s survival in space can be attributed to the protective layer surrounding the spores, shielding them from harmful UV radiation. This protective mechanism could explain how bryophytes, a robust moss group, evolved from aquatic to terrestrial plants around 500 million years ago.
Fujita expressed optimism that the study’s findings could contribute to the establishment of ecosystems on celestial bodies like the moon and Mars, potentially laying the groundwork for future space exploration missions.
[Source](https://www.cbc.ca/news/science/space-moss-9.6984791)
