Radiation-resisting hardy bugs may survive a million years on Mars

LONDON - University College London researchers have found that hardy bugs like Deinococcus radiodurans could survive dormant on Mars for over a million years, at least in theory.

Lewis Dartnell and colleagues froze the bugs to -79 Degrees Celsius, the average temperature at Mars’s mid-latitudes. The bugs were then zapped with gamma rays to simulate the dose they would receive 30 centimetres below Martian soil over long periods of time.

Calculations indicated that the bugs could live for 1.2 million years under these conditions to shrink a population of the bacteria to a millionth of its original size, reports New Scientist.

If a cell is frozen, radiation does less damage to it because the free radicals it creates are much less mobile. Dartnell’s team also isolated three new strains of bacteria from the Dry Valleys of Antarctica, where winter temperatures drop to -40 Degrees Celsius.

The hardiest of the bugs, a new strain of Brevundimonas, could persist for 117,000 years on Mars before its population would be reduced by a factor of a million, the team’s work suggests.

However, Cassie Conley of NASA cautions that even if terrestrial microbes could survive on Mars itself, they might not fare so well on the journey there.

The high vacuum in spaceflights can desiccate microbes, she said.

Conley, who makes sure NASA missions minimise the risk of contaminating other worlds with microbes, said, “The policy is that we won’t contaminate other planets or moons, because just one colonising event could screw up our ability to study indigenous life forever.”

The study appears in Astrobiology. (ANI)