First, the scientists tested the moss’s tolerance to cold. They put some plants in an ultra-cold freezer set at -80 degrees Celsius for three to five years.
Others were placed in a tank of liquid nitrogen at -196 degrees Celsius for 15 and 30 days. When the plants were defrosted, the scientists found that they regenerated, although they didn’t bounce back as quickly as samples that had been dehydrated instead of frozen.
The moss also could survive exposure to high levels of gamma radiation. Surprisingly, doses of 500 Gy seemed to boost plant growth.
Most plants would die if they were exposed to this much radiation. Humans experience severe convulsions and death when exposed to around 50 Gy.
Finally, the researchers created simulations of the conditions on Mars using the Planetary Atmospheres Simulation Facility at the Chinese Academy of Sciences.
The atmosphere they subjected the moss to was composed of 95 percent carbon dioxide, with temperatures ranging from -60 degrees Celsius to 20 degrees Celsius. There were also high levels of UV radiation and low atmospheric pressure.
After one, two, three, and seven days of exposure, the researchers saw that the moss plants achieved a 100 percent regeneration rate within 30 days.
Hydrated plants were in the simulation for one day, but they regrew more slowly than their dried-out counterparts. Still, both groups survived.
“Although there is still a long way to go to create self-sufficient habitats on other planets, we demonstrated the great potential of S. caninervis as a pioneer plant for growth on Mars,” the researchers wrote.
