Scientists find desert moss ‘that can survive on Mars’

[Don2 (Don1 Revised)]

Scientists find desert moss ‘that can survive on Mars’

Moss that grows in Mojave desert and Antarctica may help establish life on the red planet, researchers say

www.theguardian.com

It would be interesting to see this attempted in greenhouses on the Moon and/or Mars. Of course, more study is needed on this planet before investing in such a project.

 

[lpetrich]

It will still need liquid-water temperature and pressure to grow, however, and only a little bit of Mars's surface can have liquid water, and only for a little bit of the time.

From the article,

The team say their work is the first to look the survival of whole plants in such an environment, while it also focuses on the potential for growing plants on the planet’s surface, rather than in greenhouses.

...
Writing in the journal The Innovation, researchers in China describe how the desert moss not only survived but rapidly recovered from almost complete dehydration. It was also able to regenerate under normal growth conditions after spending up to five years at -80C and up to 30 days at -196C, and after exposure to gamma rays, with doses of around 500Gy even promoting new growth.

The team then created a set-up that had similar pressures, temperatures, gases and UV radiation to Mars. It found the moss survived in this Mars-like environment, and was able to regenerate under normal growth conditions, even after seven days of exposure. The team also noted plants that were dried before such exposure faired better.

“Looking to the future, we expect that this promising moss could be brought to Mars or the moon to further test the possibility of plant colonisation and growth in outer space,” the researchers write.

It needs "normal growth conditions" to grow - what are the researchers calling "normal"?

Dr Wieger Wamelink of Wageningen University, also raised concerns, including that temperatures on the red planet rarely get above freezing, making outdoor plant growth impossible, while the new study did not use Mars-like soil.

“The mosses were treated under Mars circumstances for a maximum of several days and then regrown under Earth conditions on sand,” he said. “This, of course, does not show at all that they can grow under Mars conditions.”

There is also the problem of too low atmospheric pressure in all but the lowest spots, like Hellas Planitia.

Water is not liquid for pressures below its  Triple point - pressure 611.657 Pa (6.11657 mbar), temperature 273.16 K (0.01 C).

Below that pressure, water goes directly between solid and gas, with its evaporation often called sublimation.

There is a familiar substance that does that under ordinary conditions: carbon dioxide. Its triple point has pressure 517 kPa (5.17 bar), temperature 216.55 K (-56.60 C). That's well above the Earth's sea-level atmospheric pressure: 101.3 kPa (1.013 bar).

 Atmosphere of Mars - average pressure 610 Pa (6.10 mbar)

 Hellas Planitia - it goes down 7,152 m below the topographic reference - pressure 1240 (12.4 mbar)

 

[lpetrich]

This desert moss has the potential to grow on Mars | ScienceDaily

Refers to that paper:

Tingyun Kuang, Yuanming Zhang, Daoyuan Zhang. The extremotolerant desert moss Syntrichia caninervis is a promising pioneer plant for colonizing extraterrestrial environments. The Innovation, 2024; 100657 DOI: 10.1016/j.xinn.2024.100657

It link was a bad one before today, but it now works: The extremotolerant desert moss Syntrichia caninervis is a promising pioneer plant for colonizing extraterrestrial environments: The Innovation

They tested to see how well these plants can survive by giving them Earthlike conditions. But on Mars's surface, the hostile conditions are permanent, so one will have to look for something that will grow under such conditions, rather than wait for better conditions, as this plant does.

 

[bilby]

It seems highly unlikely to me that any terrestrially evolved multicellular organism could survive on Mars; If we wanted to put Earth life onto the red planet, we would need to start with bacteria, ideally ones that would make conditions more Earth-like over time.

But that's all premature; Until we are 100% certain that Mars has no life of its own, it would be hugely irresponsible to introduce Earth life to that planet.

Everywhere that humans have introduced plant or animal species, we have subsequently found that there was fascinating and previously unknown life there, but sorry, it just got driven to extinction by our imports. Oops. And that's just on our own planet. So far.

 

[Elixir]

It seems highly unlikely to me that any terrestrially evolved multicellular organism could survive on Mars; If we wanted to put Earth life onto the red planet, we would need to start with bacteria, ideally ones that would make conditions more Earth-like over time.

But that's all premature; Until we are 100% certain that Mars has no life of its own, it would be hugely irresponsible to introduce Earth life to that planet.

Everywhere that humans have introduced plant or animal species, we have subsequently found that there was fascinating and previously unknown life there, but sorry, it just got driven to extinction by our imports. Oops. And that's just on our own planet. So far.

Just goes to show how ubiquitous expendable species are.