Search for life on Mars

The most advanced American self-propelled probe will dig the surface of Mars to look for signs of life when it lands on the red planet next month.

Curiosity, the name of the self-propelled device of the US Aerospace Agency (NASA) flying to Mars, will land on the red planet on August 5. Where it will land is the Gale hole, a region dating back to 3.5 billion years on the surface of Mars. After approaching the surface of the planet, the device will drill, excavate and analyze rock samples in search of signs of life, Space reported.

Illustration of the spectacle of the Curiosity self-propelled device landing on Mars's surface on August 5.

'The current challenge of self-propelled probes on Mars is that they have never detected any organic compounds. We know that organic molecules can exist on that planet, but the machines have not found them in the soil, 'said Alexander Pavlov, a NASA expert.

Complex organic molecules, such as those with 10 or more carbon atoms, can be reliable evidence of the existence of living organisms in the past, because they are capable of creating creature.

NASA scientists believe that the opportunity to find organic molecules at a depth of 2 cm or less is almost zero. The top layer of Mars absorbs too much cosmic radiation over billions of years, so it is very likely that organic matter has been destroyed.

'But if you dig a few centimeters deeper, what Curiosity can do, it will most likely find simple organic molecules,' the researchers said.

Some previous studies have demonstrated that cosmic radiation can only reach a maximum depth of 1.5 m in the soil. So the organic molecules below that depth can exist for several billion years.

Even if Curiosity finds simple organic molecules, that finding doesn't mean that life forms have ever appeared on Mars.

"It is possible that simple organic substances come from other sources, such as meteorites and cosmic dust ," NASA researchers explained.