New research suggests that deep beneath a glacier on Mars there lurks a salt water lake, but what kind of life could live there, and could anything currently on Earth be able to survive in its salty depths?
Because Mars once held water on it and was a much more hospitable planet than it is today, it is fully possible that ancient life may still be lingering on the red planet, whether it is still living or is now fossilized. There is also the possibility that microbes from Earth may have hitched a ride to the planet during previous missions of space exploration, and these microbes could now be dwelling in a salt water lake, according to Space.
However, scientists do not believe that it is very likely that larger animals would be found in such a salt water lake on Mars. And while there are indeed some fish, organisms, and insects here on our own planet that can survive at freezing subzero temperatures, on Mars there wouldn’t be the necessary food webs to keep such organisms alive.
Microorganisms, on the other hand, are fully able to live in hostile environments where other organisms would quickly die out, leading scientists to speculate that if there is a salt water lake on Mars, these could almost certainly survive.
— SPACE.com (@SPACEdotcom) September 18, 2018
Scientists know on Earth that microbes can withstand brine, and in fact research on halophilic microbes has shown that these organisms can easily live surrounded by high salt levels, and this includes even common table salt.
Terrestrial halophiles also are extremely hardy and have no problem enduring ultraviolet light or low temperatures, something that would be commonplace on Mars. Some halophilic microbes also may be able to survive life in a salt water lake, and these include the bacterium Halanaerobium, the fungus Aspergillus and also archaea, which are known to create methane.
The biggest threat to life on Mars, in a salt water lake or elsewhere, would be the planet’s extremely low temperatures of -70 degrees Celsius. However, this may not be as big of a barrier as people may believe as many freezers that are used on Earth are actually much colder, and these are able to hold microbial cells and biological material without a problem.
“Plants and animals such as roundworms – which are more vulnerable to damage than some microbes – have been revived from permafrost after remaining frozen for about 30,000 to 42,000 years on Earth,” as John E. Hallsworth explained.
So with regard to whether life as we know it has the ability to survive in a salt water lake on Mars, even if life may not originally begin there, it could very well be preserved for extended lengths of time.