WORLD But in this study, “even if the liquid water exists on Mars, it is unlikely found in life … “
data analysis sent by the US robot Curiosity reinforce the hypothesis that liquid water could exist on Mars, say researchers in a study published Monday in the journal Nature .
Mars lost an ocean that covered half of its northern hemisphere
A type of salt and sediment present on Mars
“We found calcium perchlorate in the soil (…), a substance that under certain conditions absorbs water vapor in the atmosphere,” says Morten Bo Madsen, co-author of the work, said in a statement of the Niels Bohr Institute at the University of Copenhagen. Perchlorate, a type of salt, point depression of water freezing, so that it remains liquid.
When darkness falls, part of the water vapor in the atmosphere condenses on the surface of the planet and ice. But calcium perchlorate is very absorbent and form with the water a “brine”, which lowers the freezing point, and allows the ice to be transformed into liquid water, adds. The soil is porous, the water seeps into the ground.
Observations of the robot, which is about to ascend Mount Sharp, in the middle of Gale Crater, also demonstrate the presence of sedimentary deposits. “This type of deposit is formed when large amounts of water flow along the crater” and join stagnant water to form a lake, “says the researcher.
A significant part of the water disappeared in space
There are 4.5 billion years, Mars contained 6.5 times more water than today and a thicker atmosphere, according to Morten Bo Madsen. But much of this water disappeared into space because Mars lost its magnetic field.
“Improbable found life on Mars”
“Even if the liquid water exists on Mars, it is unlikely that we find life on Mars, “however, the statement said. The planet offers an environment “too dry, too cold and suffered so powerful cosmic radiation that penetrate at least one meter below the surface, killing all life,” at least comparable to that all life on Earth.
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