In the TV show “Star Trek,” they made it look easy: The crew would pull out their trusty tricorder to scan a planet’s surface for biological activity.
In real life, we’re not quite there yet.
Even though scientists often take instruments into the field to measure chemical indicators like pH or the amount of chloride present, there is no single portable field device that can measure whether (microbial) life is present, then provide an initial assessment of the amount of biomass and what type of microorganisms are prevalent. But Jacqueline Goordial and her co-investigators from McGill University in Canada recently took a first step in this direction.
The research team used three miniature low-cost, low-energy instruments to directly detect and analyze life in the high Canadian Arctic. One instrument measured the color change when provided nutrient sources were altered by microbial growth, while another detected microbial colonization. The third and most powerful tool was a portable DNA sequencing device called MinION. Based on nanopore sequencing technology, the device allowed the research team to characterize microbes and determine their functional genes, even under challenging field conditions.
In fact, the team conducted their tests in the Canadian High Arctic to find out whether the devices would work at temperatures similar to those on Mars. In general, the answer was yes, even though it took Goordial’s suite of instruments days to collect the information a tricorder could scan in seconds. Also, humans were still needed to carry out all the procedures, and it’s doubtful that these particular instruments would hold up to the rigors of long-term space travel and exposure to the Martian surface. For that matter, we don’t know whether organisms on another planet would even use terrestrial DNA, or whether their genetic code could be sequenced.
But this is a promising step in the right direction. And the technology might be useful on Earth, where it could do an initial assessment of biomass in places that are inhospitable. The first use of a real tricorder, then, might be on our own planet.