For 18 months, the organisms were subjected to Mars-like conditions. The atmosphere was 95% carbon dioxide, 1.6% argon, 0.15% oxygen, 2.7% nitrogen, and 370 ppm water, with a pressure of 1,000 pascals. Additionally, they were exposed to ultra-violet radiation similar to that on Mars.
And they returned alive.
European scientists recently tested the viability of Antarctic fungi in both Martian and space conditions aboard the International Space Station (ISS).
In the McMurdo Dry Valleys of Antarctica, only the fittest organisms survive. And usually, they’re microorganisms. A handful of years ago, scientists collected samples of the fungi Cryomyces antarcticus and Cryomyces minteri. Placed in cells 1.4 cm in diameter, the fungi were situated outside the ISS’s Columbus module.
“More than 60% 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 Rosa de la Torre, of Spain’s National Institute of Aerospace Technology.
However, less than 10% of the retrieved fungi samples exposed to Martian conditions were capable of proliferating and forming colonies, the researchers reported.
The findings were published in Astrobiology.
The study was performed as part of the European Space Agency (ESA)’s Lichens and Fungi Experiment (LIFE).
“The results help to assess the survival ability and long-term stability of microorganisms and bioindicators on the surface of Mars, information which becomes fundamental and relevant for future experiment centered around the search for life on the Red Planet,” said de la Torre.
Additionally, researchers studied the viability of lichen species Rhizocarpon geographicum and Xanthoria elegans. Both lichens are found in high-mountain regions, such as Spain’s Sierra de Gredos and Austria’s Alps. As with the fungi specimens, some of the lichen samples were exposed to space conditions, while others were exposed to Martian conditions.
In space conditions, temperatures fluctuated between -21.5 and 59.6 C, and galactic-cosmic radiations reached up to 190 megagrays. The lichen samples exposed to Martian conditions showed twice the metabolic activity than those exposed to space conditions.
Thirty-five percent of the fungal cells exposed to space conditions kept their membranes intact.