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Lichens are unique forms of life, formed by a symbiotic relationship between a fungus providing protection and nutrients, and an alga or cyanobacterium providing food through photosynthesis. While lichens may seem unremarkable in appearance, they possess remarkable resilience and can even withstand the extreme conditions of space.

During a duration of 18 months, lichens were able to withstand and thrive in the harsh conditions of the International Space Station’s exterior, including vacuum conditions, lack of water, extreme temperatures, and exposure to intense radiation and ultraviolet rays from the sun. They continued to perform photosynthesis despite these challenges.

After being exposed to a simulated Martian environment on Earth, lichens were found to have survived and remained active. This suggests that life may be able to exist on Mars, despite its harsh conditions of extreme dryness, cold temperatures, low atmospheric pressure, and high levels of radiation. Lichens have been observed to withstand radiation levels that are 12,000 times the lethal dose for humans, although their reproduction can still be affected. Interestingly, bacteria that were also subjected to the simulated Martian environment did not survive. It has even been speculated that lichens may have played a role in spreading life to other planets through hitching rides on meteorites, comets, or asteroids.

Source: theguardian.com