The dream of finding life on Mars may now be a step closer to being realized after a series of experiments here on Earth.
Scientists at Northwestern University and the Uniformed Services University have conducted many experiments where they directed high levels of radiation at bacteria and fungi to see how long these organisms could survive on Mars.
Their surprising results are published in the journal Astrobiology
They concluded that the bacterium deinococcus radiodurans could live for hundreds of millions of years on the red planet.
Due to the bacteria’s resilience, it was given the nickname “Conan the Bacterian” after the protagonist “Conan the Barbarian”.
Harsh living conditions on Mars
Living conditions on Mars are, to say the least, extremely bad. The planet is completely dry and devoid of vegetation, has no magnetic field and an extremely thin atmosphere.
On the surface, there is a simple barrage of charged particles and ultraviolet rays that would kill most living things in a short time.
In their experiments, the scientists shot protons and gamma rays at six types of bacteria and fungi, simulating conditions on Mars.
The most hardy organism was found to be deinococcus radiodurans. Specifically, it was found that this bacterium can withstand 140,000 gray, a unit of measurement for received radiation, in Martian conditions but deep in dry, frozen soil. This is 28,000 times more than any human could survive.
If the bacterium deinococcus radiodurans were placed directly on the surface of Mars, it would die in a few hours.
However, if the bacterium is only 10 centimeters deep, it could survive for 1.5 million years.
The scientists tested these bacteria even more and concluded that at a depth of 10 meters in Martian soil, they could survive for up to 280 million years.
It is the structure of the genetic mass that causes the radiation resistance of the bacteria. Its chromosomes and plasmids are linked in such a way that the bacterium can withstand damage caused by radiation.
The search for bacteria
The first soil samples from Mars are expected to return to Earth in 2033, and in them scientists will carefully search for ancient, radiation-resistant bacteria.
