Mars is a hostile planet. Its distance from the sun makes it cold and barren – average daily temperatures on Mars are around -60C and this falls to – 126C in winter near the poles.
What’s more the thin Martian atmosphere means the planet is bombarded with intense life-destroying radiation.
Scientists believe a handful of single celled creatures could have what it takes to survive on the Red Planet
And there’s little oxygen there. In fact 95% of the atmosphere is made up of carbon dioxide.
Yet scientists believe that a handful of simple single celled creatures found in some of the most extreme places on Earth – sulphurous lakes and permafrost for instance – could have what it takes to survive on the Red Planet.
To vet the prospective applicants, astrobiologists are replicating Martian conditions in the laboratory, zapping the microbes with gamma and UV radiation, and freezing them to see if they survive. Some microbes have even been taken up to the International Space Station for the ultimate test of how they cope off our planet.
As a result the researchers now have a list of potential candidates that could survive the Red Planet’s sub zero temperatures, vacuum conditions and intense solar radiation. So what are the candidates like?
The most obvious potential Martian is nicknamed “Conan the Bacterium” for its toughness
The most obvious potential Martian is Deinococcus radiodurans, a bacterium that is the most radiation resistant lifeform that has ever been found. The species is nicknamed “Conan the Bacterium” for its toughness. The almost indestructible microbe can survive doses of ionising radiation thousands of times stronger than those that would kill a human.
The bacterium isn’t phased by extreme temperature either. Scientists chilled D. radiodurans to -79C, the average temperature at Mars’s mid-latitudes. Then they bombarded the cells with gamma rays to simulate the dose they would receive living under 30cm of Martian soil over long periods of time. The beings were so hardy that researchers estimated it would take 1.2 million years under these conditions to shrink a population of the bacteria to a millionth of its original size.