What do you think of this fact?
You’ve probably walked past those crusty patches on rocks and tree bark a thousand times without noticing. But lichens are some of the toughest living things on Earth. So tough that scientists sent them to a fake Mars.
A lichen is a roommate situation
A lichen isn’t a single organism. It’s a partnership: a fungus living closely with algae or cyanobacteria. The fungus provides shelter and structure, while its partners make food through photosynthesis. That teamwork is why lichens are famous for shrugging off extreme dryness.
A month on lab Mars
The German Aerospace Center (DLR) wanted to find out just how tough. In Berlin, planetary researcher Jean-Pierre de Vera and his team put lichens from high mountains and polar regions into a Mars simulation chamber. Conditions inside matched the Red Planet:
- an atmosphere of 95 percent carbon dioxide and 4 percent nitrogen
- air pressure of just 6 millibars
- temperatures swinging between minus 50 and plus 23 degrees Celsius
- radiation from ultraviolet to infrared
After 34 days, the lichens were still alive. Better yet, they kept photosynthesizing. They got their water from condensation that formed during the simulated Martian mornings and evenings, doing best when tucked into rock niches and cracks in the soil.
Even real space isn’t enough
Back in 2005, the European Space Agency (ESA) launched two lichen species, map lichen and elegant sunburst lichen, on the Foton-M2 capsule. For 14.6 days they were exposed to vacuum, huge temperature swings, the full spectrum of solar UV and cosmic radiation. Back on Earth, the analysis showed they had all survived, and their photosynthesis worked just like before.
Lichens weren’t the only ones in DLR’s Mars chamber. Some cyanobacteria also made it through the experiment and stayed active.
So will lichens be growing on Mars soon? Not so fast. The researchers themselves admit that one month in a lab leaves open what happens over much longer stretches of time. It’s still a big deal for the search for life: if Earth organisms can handle these conditions, life on Mars could have held out in sheltered niches.
That lichen on your garden fence is basically an undercover astronaut.