Near the summit of Costa Rica’s Poás Volcano is one of Earth’s most acidic lakes, bright blue and full of toxic metals. The harsh conditions of Laguna Caliente, where temperatures can fluctuate between 100 degrees Fahrenheit and 194 degrees Fahrenheit, are where a few lucky scientists go to learn more about Mars.
Frequent phreatic eruptions occur when groundwater is heated by volcanic activity, releasing explosions of ash, rock, and steam. The microbes have found a way to live in this environment, one of the most hostile on our planet, according to multiple studies of the lake and new research published last week in Frontiers in Astronomy and Space Sciences.
Poás Volcano, located in the middle of the Costa Rican rainforest, erupted most recently in 2017 and 2019. The area immediately around the Volcano is devoid of life due to the toxic gases it releases. Wang and his collaborators hiked to the Volcano in November, a month after the crater lake reformed. They were mindful of where they stepped in the loose soil caused by acidity breaking down the surface material. Parts of the lake boiled and volcanic openings called fumaroles belched out hot sulfurous gases.