Demonstrating that scientists can extrapolate with the best of them, researchers have speculated that long dormant microbes on the Red Planet might reawaken with the introduction of liquid water.
The Washington State University team, led by astrobiology boffin-in-chief, Dirk Schulze-Makuch, found that microbes lurking in the soil of the hyperarid Atacama desert in Chile were capable of going dormant during decade-long periods of drought before reactivating and multiplying upon the arrival of rain.
Boffins regard conditions on Atacama as the closest it is possible to get to Martian conditions on Earth, although the surface of Mars is even harsher than the Atacama (less water, higher levels of irradiation and an atmosphere worse than a Russ Abbott tribute gig).
Current evidence suggests deeper soil layers on Mars may have higher levels of water activity while being less exposed to nasties such as temperature variations - ideal for microbial life.
Rainfall occurred while Schulze-Makuch’s team were studying how organisms adapt and survive in the Atacama. Since this was highly unusual, the team whipped out a handy set of sterilised spoons and scooped up soil for analysis.
The results showed an explosion of biological life that returned to a dormant state as the moisture disappeared.
Boffins believe the microbes have adapted to the point where survival over hundreds or even thousands of years is possible in conditions very similar to those found on Mars.
Until someone arrives on the surface of the Red Planet with a drill capable of going deeper than the rock botherers of rovers have managed so far, and a set of instruments to perform the analysis, the theory will have to remain informed speculation.
ESA’s ExoMars rover, due for launch in 2020 on a Russian Proton booster, will be able to extract samples from up to 2 metres beneath the Martian surface.
Analysis in the onboard lab may be able to spot elusive organic substances.
The idea that pesky organisms might awaken on Mars upon the arrival of water or oxygen is explored in the absolutely terrible Val Kilmer vehicle detailed treatise on Martian exploration, Red Planet.
Boffins will be crossing their fingers that future explorers do not face the same tribulations as those fictional astros. ®