The vast sand dunes, which are near the north pole of Mars is not just frozen relics of the past, they move and change every Martian year, as shown by observations.
High-tech cameras mounted on the Martian satellite reconnaissance Mars Reconnaissance Orbiter has identified the area of dunes UK sizes, which are among the most dynamic on the Red Planet.
The cause of dynamism, as stated in the report, in the journal "Science", was carbon dioxide, which freezes solid bodies in the dunes each winter. When it all starts to thaw in the spring, the gas creates a state of instability, thus causing, landslides sand.
Area of dunes at high northern latitudes of Mars were first identified as a result of Mariner 9 mission, launched in 1971. But only by taking advantage of the experiment High-Resolution Imaging Science Experiment (Hirise), in orbit of Mars, in the end managed to capture the dynamic nature of the dunes.
"In the course of a scientific experiment obtain high-resolution images observation of seasonal processes were conducted for several years, a period when we have seen for a long time, only strange point and strips, which were formed especially in the sand dunes during their defrost" - said Alfred McEwan (Alfred McEwen), a planetary geologist at the University of Arizona, who is the head of Hirise.
A series of images taken in the areas of dunes over two Martian years equals almost four years on Earth, after the disappearance of the annual ice clearly shows the changes that have taken place on the surface of Mars.
"So, what we have noticed recently, watching from year to year by sand dunes, is the formation of new gullies and new channels, which speaks about the activity, which we did not know for a long time" - said Professor news BBC BBC .
"There is a lot of discussion about being able to characteristics that we see on Mars formed in the climate prevailing at present on Mars, or it requires other conditions. Our data lead to a better understanding of where and when the sand moves that important for both the weather and for the surface properties of Mars, calibrating various models that can be used to understand the life of Mars in the past and the present. "