14 DAY TRIAL // A new study conducted on images sent back by the European Space Agency's (ESA) Mars Express orbiter hints at the possibility that microbial life on the Red Planet may endure inside landscape features called pit-chains.
As seen to the left, these structures can be found on the flanks of some of the solar system's largest volcanoes. They may be capable of hosting not only microbial life indigenous to Mars, but also future astronauts that will head out to explore the Red Planet.
Radiation levels on the surface are very high, but studies have recently indicated that this is not the case inside the pit-chains. The thick layers of rock making up their walls block a significant portion of the radiations that would otherwise make their way to the pit-chain floor.
This image of such structures was collected on June 22, 2012, above the vast Tharsis region on Mars. This area contains three of the largest and most voluminous volcanoes in the entire solar system, including Alba Mons (Alba Patera).
The photograph covers an area inside the Tractus Catena region of the Arcadia quadrangle. “Tractus Catena sits on its southeastern flank of Alba Mons and the pit-chains in that region are a series of circular depressions that formed along fracture points in the Martian crust,” an ESA statement explains.
Geologists say that pit-chains can develop from volcanic sources, when magma flowing down the slopes of a mountain solidifies at the surface, but continues to flow in tube-like structures underground. When the eruption stops, those tubes are emptied.
In time, erosion and other processes eat away at the tunnel's ceilings, portions of which eventually collapse. As this happens, sections of the lava tubes are exposed to the harsh environment on Mars. Such structures exist on Earth and the Moon as well, but they can have other origins.
“Some of Earth’s most famous examples are the network of ‘cenotes’ on the Yucatan peninsula of Mexico. These deep natural pits form when the surface limestone rocks collapse, exposing the groundwater underneath,” the ESA press release adds.
“This origin is the most interesting in the context of the search for microbial life on Mars. If there are any cave-like structures associated with the pits, microorganisms could have survived, protected from the harsh surface environment,” the document concludes.