Results are back from one of the latest experiments hosted on the International Space Station (ISS), with researchers from Spain's National Institute of Aerospace Technology (INTA) using the facility to study how hardy fungi species, collected from the Antarctic, cope under simulated Martian conditions. The results are helping scientists gain insights relevant to the search for life on the Red Planet.

The ISS is a hotbed for insightful studies, hosting numerous experiments that significantly improve human understanding of the long-term effects of space flight. Previous work has looked at how quickly medicines degrade in space, how microgravity effects the human immune system, and much more.

The new study centered on two species of fungi known as Cryomyces antarcticus and Cryomyces minteri. Types of cryptoendolithic microorganisms, the fungi were harvested from cracks in rocks in the McMurdo Dry Valleys in the Antarctic Victoria Land – one of the driest and most hostile environments on the planet.

From there, the samples made their way up to the ISS for an 18-month experiment. In individual 1.4 cm (0.55 in) diameter cells, the fungi were placed on a European Space Agency-developed EXPOSE-E experiment platform, which itself was placed outside the Columbus module on the space station. The work forms part of the wider Lichens and Fungi Experiment (LIFE), which aims to examine how various organisms cope with extreme conditions in space.

Over a period of a year and a half, the fungi were exposed to conditions similar to those found on Mars, with an atmosphere of 95 percent CO2, and a pressure of 1,000 pascals. Optical filters were used to expose some of the samples to ultraviolet radiation levels similar to the Red Planet, while others experienced lower levels of the radiation, and a control group was left unexposed.

Once the experiment was complete, the researchers found that an impressive 60 percent of fungi cells had survived the Mars-like conditions, with their cellular DNA remaining stable. While fascinating in their own right, the findings are providing scientists with new information that will help in the search for life on Mars.

"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 experiments centered around the search for life on the Red Planet," said researcher Rosa De la Torre.

The results of the study are published in the journal Astrobiology.