According to the latest assumptions of scientists, intriguing dark stripes on Mars can be proof not of liquid water, but of some other phenomenon. These long and narrow repeating oblique structures were first discovered in 2011 on images obtained by the MRO Martial Reconnaissance Apparatus, which was launched into orbit around the Red Planet by the US Space Agency NASA.
Some researchers believe that such structures could be formed by streams of salt water, and therefore are signs of a potentially livable environment. This idea was supported by most NASA scientists after it was announced that thanks to the scientific tools of the Martian Reconnaissance Apparatus, hydrated salts in these structures were discovered.
But liquid water is not the only possible explanation for the origin of such linear inclined structures. Some researchers suggested that they could have been provoked by seasonal freezing of carbon dioxide, while others argue that these “lines” are nothing but avalanches of dry mud and sand.
A new study, which was published on Monday, March 20, in the journal Nature Geoscience, sets out the case for the latter hypothesis. A team of researchers led by Frederick Schmidt from the University Paris-South 11 in France modeled these structures. During this research it was found out that only sunlight can cause landslides. This phenomenon is called “thermal creep”.
Computer modeling has shown that solar heating destabilizes the material of inclined structures causing landslides.
“Due to solar insolation in the ground, there is a rise in temperature, and thus the air moves to the porous space of the ground, which in turn destabilize the grains of sand. This effect is greatly enhanced by the presence of a shadow from the boulders, “Schmidt said.