Antarctic fungi could be able to colonize Mars

Sunday, February 07, 2016 by: David Gutierrez, staff writer
Tags: Antarctic fungi, Mars colonies, extremophiles

---

(NaturalNews) Fungi from the rocks of Antarctica may be tough enough to survive on Mars, according to the results of a study published in the journal Astrobiology.

The research is part of an effort to discover what types of life forms may have previously lived on Mars, or may be there still.

"The most relevant outcome was that more than 60 percent of the cells of the endolithic communities studied remained intact after 'exposure to Mars', or rather, the stability of their cellular DNA was still high," said researcher Rosa de la Torre Noetzel of Spain's National Institute of Aerospace Technology.

Organisms also survive in space

Researchers collected two species of "cryptoendolithic" fungi (Cryomyces antarcticus and Cryomyces minteri) from the McMurdo Dry Valleys in the Antarctic Victoria Land, a cold, dry area thought to be Earth's most similar environment to Mars. The strong winds and frigid temperatures of this region mean that almost nothing lives there except for tiny microorganisms inside rocks.

Yet Mars is far more hostile to earthly life than even Antarctica, with an atmosphere high in radiation and lacking in oxygen. To discover how the fungi would fare in such an environment, the researchers developed a special platform called EXPOSE-E to be tough enough to survive exposure to extreme conditions. The fungi were paced in EXPOSE-E and then sent up to the International Space Station.

For 18 months, one group of fungus was exposed to Mars-like conditions, including pressure of 1,000 pascals, ultraviolet radiation higher than 200 nanometers, and an atmosphere of 95 percent CO₂, 1.6 percent argon, 2.7 percent nitrogen, 0.15 percent oxygen and 370 parts per million of water.

After 18 months, 60 percent of the fungal cells still had significant DNA integrity; 10 percent were able to proliferate and produce new fungal colonies, which the researchers considered surprisingly high.

The research was part of the ongoing Lichens and Fungi Experiment (LIFE). As part of that experiment, the same species of cryptoendolithic fungi were also exposed to more intense conditions equivalent to those found in outer space. These included cosmic radiation of up to 190 megagrays and intense temperature fluctuations between -21.5 and 59.6 degrees Celsius. Even after 18 months of these extreme conditions, 35 percent of fungal cells were still intact.

Another LIFE experiment, which only has preliminary results available, consisted of testing lichens from Spain and the Austrian Alps under Mars- and space-like conditions. The lichen also appeared to fare surprisingly well.

"The results help to assess the survival ability and long-term stability of microorganisms and bioindicators on the surface of Mars," said De la Torre of the ongoing research. "Information which becomes fundamental and relevant for future experiments centred around the search for life on the Red Planet."

Life already on Mars?

Learning what sort of earthly organisms might survive on Mars doesn't just help scientists figure out what native Mars life might look like; it also gives them a sense of what earthly life might already have established itself on the Red Planet.

Decades of unmanned trips to Mars have almost certainly seeded the planet with extremophiles from our own world, NASA has said. That's because Mars is much more conducive to life, and earthly organisms are also much tougher, than was previously assumed.

Following the 2012 launch of the Curiosity Mars rover, scientists swabbed the cloths used to "decontaminate" the rover and discovered a host of fungal and bacterial DNA. They are now researching many of these species on the International Space Station, to see which of them are likely to have survived the trip. The unsurprising news: Probably most of them.

"We know there's life on Mars already because we sent it there," said John Grunsfeld, the associate administrator of the agency's Science Mission Directorate, in October, following the discovery of surface water on Mars.

Sources for this article include:

ScienceAlert.com

NewYorker.com