Dusty clouds at the martian North Pole
Mottled clouds of dust within a martian dust storm are visible on the right of this image from ESA’s Mars Express. The evolution of this storm was tracked by the Visual Monitoring Camera on 29 May 2019.
This storm formed at the North Pole of Mars during the active springtime season. The bright ice cap of water ice and carbon dioxide ice is visible on the left in contrast with the darker storm. The heat of springtime causes the layer of carbon dioxide ice to sublimate, leaving behind the water ice underneath.
The storm is made up of small dust cells, forming the granular texture visible in the image. By tracking the position of the cells of dust within the storm, the wind speed was measured to be up to 140 km/h. Prevailing winds elongate the shape of the cells and the shape of the arms of the storm.
