Antarctic find boosts prospects for Mars life
By Richard Stenger
(CNN) -- The unexpected discovery of organisms buried underneath a dreary stretch of Antarctic desert has bolstered hopes that life could exist in similar conditions on Mars, scientists announced this week.
Canadian and New Zealand researchers were digging in extremely cold, rocky and dry soils dating back millions of years when they chanced upon hardy colonies of fungi and bacteria.
The microorganisms thrived in soil with salt concentrations as high as 3,000 parts per million, according to William Mahaney of York University in Ontario, Canada.
"That's like vodka. That's so much salt that temperatures can drop to minus 56 degrees Celsius before there's frostbite," he said.
Usually, life avoids such briny salts, but in the dry valleys of Antarctica, where conditions most resemble those of Mars, the conditions actually can prove advantageous to biological organisms.
The salts considerably lower the freezing point, meaning that despite the big chill water can remain in liquid form, which all known life forms require.
Like Antarctica, the availability of liquid water would prove a challenge for critters on Mars. But geologic conditions over the eons could have produced similar salty brines on the red planet, according to the research team.
"Although these [super-cooling] processes are not fully understood on Earth, the fact that they occur in Antarctica shows the possibility that they also might occur on Mars," said Victor Baker, a planetary geologist at the University of Arizona in Tucson who collaborated on the study.
In recent decades, exotic life forms that endure unbelievably punishing conditions have been discovered on Earth. So-called extremophiles have turned up underneath thick layers of lake ice, inside steaming volcanic pools and along sulfur-belching fissures at the bottom of the ocean.
If future missions search for such organisms of Mars, Antarctic soil studies could help narrow down candidate sites, the researchers said.
The findings were reported in Icarus, an international journal of solar system studies that the American Astronomical Society publishes.
SPACE TOP STORIES:
NASA starts countdown to Mars mission
Shuttle probe could take six months
Shuttle widows grasp faith, each other
EPA approves new modified corn
Mexico saves island from tourism build-up
|Back to the top|