Welcome to brain Stuff from how Stuff Works, Hey, brain Stuff, Lauren Vogel bomb here. When it comes to searching for microbes on Mars, sending a robotic rover to the most arid environment on Earth is a fine place to start. As described in a study recently published in the journal Frontiers and Microbiology, a team of researchers explored the extreme environment of Chile's Atacama Desert. They wanted to develop strategies that future robotic explorers could use to seek out the
hiding places of Martian microbes. Both NASA and the European Space Agency will launch their first life hunting rovers to the Red planet, the Mars Exo Mars Rover missions, respectively, so mission managers will need to know where to look. The Atacama Desert is about as extreme as it gets for life to eke out an existence, and not only is the region bone dry, the core of the desert doesn't get any rainfall for decades at a time, but because of its elevation, it also receives high levels of
damaging ultraviolet radiation. Plus the soil is extremely salty. These factors should make the Atacama Desert toxic for life, but according to team leader stuff In Pointing, a professor at Yale and US College in Singapore, some of the bacteria just below the surface quote survive right at the limit of habitability, and this is very good news for the
prospect of finding microbes on Mars. Pointings team deployed an autonomous rover mounted drill and sampling device in the Atacama Desert to see if it could extract soil samples containing microbes down to a depth of eight centimeters that's a little over two and a half feet. As a comparison, samples were also dug up by hand through DNA sequencing. The researchers found that the bacterial life and the samples from both methods were similar, confirming that these hardy bacteria
exist and the autonomous extraction method was successful. This test run shores up hope that if similarly hardy microbes also thrived just below the Martian surface, a robot could find them. However, finding microbial biosignatures on Mars could be very challenging for a remotely operated Mars rover. The researchers found that the subsurface population of bacteria were extremely patchy, correlating with increased
salt levels that restricted the availability of water. Pointing put it this way, The patchy nature of the colonization suggest the rover would be faced with a needle in a haystack scenario. In the search for Martian bacteria, previous studies have described the ubiquitous population of relatively unremarkable photosynthetic bacteria that populate the surface of the desert in Chile. These
are microorganisms that get their energy from sunlight. Things start to get a lot more interesting and indeed more alien, just below the surface, Pointing said, we saw that with increasing depth, the bacterial community became dominated by bacteria that can thrive in extremely salty and alkaline soils. They in turn were replaced at depths down to eighty centimeters by a single specific group of bacteria that survived by metabolizing methane.
These specialized microbes have been found before in deep mind shafts and other subterranean environment, but they've never been seen beneath the surface of an arid desert. Pointing said, the communities of bacteria that we discovered were remarkably lacking in complexity, and this likely reflects the extreme stress under which they develop. Finding highly specialized microbes that can thrive in the extremely dry,
salty and alkaline Mars. Like soils in the Atacama Desert suggest methane utilizing bacteria could also thrive on the Red planet. Elevated levels of methane have been observed on Mars by various spacecraft over the years, most recently measures made by NASA's Curiosity Rover, and that's a big deal. On Earth, biological and geological processes generate methane, and in turn, microbes
can metabolize methane for energy. The discovery of methane in the Martian atmosphere could mean there's some kind of active biology going on underground. To confirm this, we need microbe seeking missions that will drill below the surface, and now we have a strategy to track them down. Should microbial life be found on Mars, it would undoubtedly be the most significant scientific discovery in human history. But in the proud human tradition of naming new things, what would we
call our newly discovered Martian neighbors? Would we just copy the system of how we name life on Earth? Pointing said, the way we assign Latin names to terrestrial bacteria is based on their evolutionary relationship to each other, and we measure that using their genetic code. The naming of Martian bacteria would require a completely new set of Latin names at the highest level, if Martian bacteria were a completely separate evolutionary lineage, that is, they evolved from a different
common ancestor to Earth bacteria in a second genesis event. Granted, if we find the genetic code of Mars life to be similar to Earth life, it could be that life was transferred from Earth to Mars in the ancient past via a massive impact, a mechanism known as pan spermia. But if we find a truly novel genetic code that emerged on Mars, the implications for our understanding of life
would be profound. Pointing said, if we find truly native Martian bacteria, I would love to name one and call it planet a desert a supersities, which translates in Latin to survive on the desert planet. Today's episode was written by Ian O'Neill and produced by Tyler Clain for iHeartMedia and How Stuff Works. For more on this and lots of other hardy topics, visit our home planet how stuff Works dot Com.