On the occasion of the winter holidays, NASA published a series of pictures. They show winter on Mars.
Frost-covered dunes in the north polar region of Mars. Source: NASA/JPL-Caltech/University of Arizona
The axis of rotation of Mars is inclined to the plane of its orbit at an angle of 25 degrees, which is very close to the value of the inclination of the Earth’s axis. That is why the Red Planet is experiencing a similar cycle of changing seasons. However, this is where the similarities between the planets actually end. During winter, the temperature at the Martian poles drops below -125 °C. This causes carbon dioxide from its atmosphere to settle on the surface in the form of dry ice.
Images taken by MRO show frost-covered Martian dunes and crater slopes. It mainly consists of dry ice. Water ice can also be found at the Martian poles. However, its main deposits are still hidden under the surface.
Can it snow on Mars? According to researchers, yes. But this happens only at the poles of the planet during the coldest nights. That’s why we don’t have pictures of Martian snowfall yet. At the same time, it should be borne in mind that Martian snowflakes consist of the same dry ice. They have an unusual for us cubic shape and very small dimensions – smaller than the thickness of a human hair.
With the onset of spring, dry ice begins to sublimate. This leads to peculiar eruptions at the poles. Jets of carbon dioxide erupting from beneath the surface raise geyser-like fountains of dark dust. It then settles, creating various whimsical formations. The MRO images also show unusual polygonal formations at the Martian poles. They were formed when water ice split the soil into polygons.
According to the materials https://www.jpl.nasa.gov