Beneath the extremely dry surface of Chile’s Atacama Desert, scientists have discovered a functional community of microorganisms that challenges what we thought was possible for life.
While the ground above remains one of the harshest environments on Earth, there is a ‘hidden oasis’ located almost two meters below, protected from high solar radiation and complete drying out. This underground community consists mainly of unique bacteria that obtain the moisture necessary to survive from minerals. The researchers used the latest DNA sequencing and geochemical techniques to reach this result. Their work shows that life can flourish without any contact with the surface.
This discovery not only changes our view of where life could exist on Earth, but also provides valuable insights into the search for similar forms of life on Mars or other barren planets.
Scientists have discovered secret underground life two meters below the Atacama Desert in Chile
As reported in the journal PNAS Nexus, a team of scientists in the Yungai Valley discovered a wide range of microbes living two meters below the surface. This area is the driest part of the Atacama Desert. Surface organisms depend on rare rainfall, but these underground microbes do not depend on the atmosphere at all.
The researchers used advanced molecular tools to show that these bacteria are not just inactive spores. Instead, they form an active, metabolically efficient ecosystem that thrives in constant darkness.
How do gypsum pores sustain life in oases?
The survival of this hidden oasis is possible thanks to the presence of vesicular gypsum. This mineral contains small pores that capture portions of water and act as a storage site for microbes. Actinobacteria, which are hardy taxa, make up most of this community, according to the journal PNAS Nexus.
They learned how to use the moisture associated with minerals, which allowed them to live in places that were previously considered barren.
Why are scientists searching under the surface of Mars?
This discovery gives us a clear example on Earth for Mars exploration. Mars has harsh conditions with deadly radiation and freezing temperatures, so scientists believe that any life there would likely exist below the surface, like what we see in the Atacama Oasis. The discovery of habitable spaces two meters below the most Mars-like region on Earth indicates a paradigm shift.
Future planetary missions should focus on subsurface sampling to search for signs of life beyond our planet.
The team used salt and water chemistry to track ancient life
The research team took steps to rule out surface contamination as a cause of their findings. They used “genomics” and “geochemistry” methods for this purpose. As reported in the journal PNAS Nexus, by examining salt levels and determining the age of water trapped in minerals, they concluded that these microbes were present in the soil over geological timescales. Their presence was not affected by the current surface climatic conditions.