A circular sandbox captured in the northern hemisphere of Mars. Photo: NASA/JPL/UArizona
Although most of the images of Mars show us barren and rocky landscapes, some regions show that the red planet is more pleasant than usually thought. An example of this is new satellite images taken by NASA’s MRO probe.
The Mars Reconnaissance Orbiter (MRO), through its HiRise high-resolution camera, has captured impressive almost circular sand dunes that evoke the appearance of giant black balls embedded in the desert located in the northern hemisphere of Mars.
According to a statement from the University of Arizona in charge of the HiRise camera program, it is “unusual” to find sandstones with such round shapes.
Most of the dunes have a round shape, which is unusual for scientists. Photo: NASA/JPL/UArizona
“They are still slightly asymmetric, with steep slide faces at the southern end,” which is possible because Martian winds blow sand in that direction, they said.
Although they show that the winds are variable, they could not find an explanation for the shape of these dunes.
Satellite image without access. Photo: NASA/JPL/UArizona
The images were taken as part of MRO’s monitoring of 60 different locations to record the melting of the cold as the northern hemisphere of Mars reaches the end of its winter season.
Like Earth, the red planet has four seasons: summer, spring, fall and winter. The previous image of the dunes captured by the HiRise camera shows the height of the cooler season.
Dunes image taken in winter. Photo: NASA/JPL/UArizona
move the dunes
Since 2006, the MRO observatory has studied the orbits and sand dunes on Mars to help scientists understand their displacement and how they affect weather patterns.
So far, data from the HiRise camera indicates that sands on Mars move from the equator toward the poles at a rate of 1 meter per Martian year (687 Earth days).
By comparison, the fastest dunes on Earth, such as those in North Africa, move at a rate of 33 meters per year.
Mars’ atmosphere is so thin that its average surface pressure is only 0.6% of that at our sea level. As a result, sediments move more slowly on the Martian surface.