Study finds Liches are resilient to simulated Mars atmosphere exposure

According to a new study from the Space Research Centre of the Polish Academy of Sciences, certain lichen species can withstand a 50 Gy (gray) Mars-like condition expected at a 50 Gy (gray) X-ray radiation dose of strong solar activity over a year on the surface of Mars.

Liches live in a wide variety of ecosystems around the world, but are especially important in extreme environments such as hot deserts and cold polar regions.

They are known as extremes and can survive under extreme temperatures, intense radiation, and prolonged water shortages.

The prominent ability of lichens to withstand harsh conditions led to the suggestion that it is suitable for survival in extreme environments of outer space.

The successful life strategy of lichen depends on the symbiotic relationship between fungi and algae or cyanobacteria, allowing them to colonize extreme terrestrial habitats where other multicellular organisms cannot survive.

The key to understanding their impressive resistance lies in the “stress tolerant” organisms, namely the characteristics of low nutritional requirements for metabolic rates and extended lifespans. These are further supported by radiation screening, heat dissipation and antioxidant protection.

Moreover, they can even deal with long periods of water shortage and total lack of liquid water.

This is associated with a lack of ability to regulate moisture content, allowing long-term, severe dryness without damage from dormant states, but can withstand high levels of UV/photosynthetic active radiation and extreme temperatures associated with drought conditions.

Mars is the main focus of interest in astrobiology due to the presence of water and the related possibilities of life.

The current atmospheric conditions on Mars keep people at bay, and the potential habitat for existing living is limited.

Nevertheless, during more favorable climate times, habitable environments may be present below or on the surface.

These niches can serve as isolated habitats that protect against harsh conditions.

The atmosphere is mainly composed of carbon dioxide (95%), but the effectiveness of greenhouse warming is limited.

Mars’ temperature is mainly below the freezing point of water, with atmospheric pressure of 6 mbar.

As a result, a significant portion of Mars’ existing water is ice and atmospheric water vapor. However, certain amounts of water may be present temporarily as liquid water.

Both ionizing radiation and deindependence always reach the surface of Mars and pass through the Mars atmosphere much easier than Earth.

This factor is most restrictive in the Martian habitability context, as ultraviolet and ionizing radiation are very harmful to living things.

“In our study, lichen symbiotic fungal partners remained metabolically active when exposed to atmospheric conditions like Mars in the dark, including the expected X-ray radiation levels on Mars, which are expected to have strong solar activity over a year.”

In their study, the authors focused on two lichen species, diploschistes muscorum and Setoria Acleattaselected for different properties and exposed to Mars-like conditions for 5 hours in simulations of planetary atmosphere composition, pressure, temperature variation, and X-ray radiation.

The findings suggest particularly lichens diploschistes muscorumdespite the high doses of X-ray radiation associated with solar flares and energy particles reaching the surface of the planet, it can survive on Mars.

These results challenge the assumption that ionizing radiation is an insurmountable barrier to Mars’ life and set the stages of further research into the possibilities of extraterrestrial microorganisms and symbiotic survival.

“Our study is the first to demonstrate that the metabolism of fungal partners in lichen symbiosis remains active while in an environment similar to the Martian surface,” Dr. Sukibauwa said.

“We found it diploschistes muscorum It was able to carry out metabolic processes and effectively activate the defense mechanism. ”

“These findings expand our understanding of biological processes under simulated Mars conditions and reveal how hydrates respond to ionized radiation.

“Ultimately, this study will deepen our knowledge of the adaptation of lichens and the possibility of colonizing the extraterrestrial environment.”

Survey results It will be displayed in the journal IMA bacteria.

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K.Skubała et al. 2025. Ionized Radiation Resilience: How metabolically active lichens endure simulated exposure to the Martian atmosphere. IMA bacteria 16:E145477; doi:10.3897/imafungus.16.145477