A recent batch of images taken by NASA’s Mars Reconnaissance Orbiter and the European Space Agency’s (ESA) Mars Express orbiter has revealed a striking “winter wonderland” on the Red Planet.
The photos show snow-like white spots dotting the Martian landscape, particularly in the Australe Scopuli region near the planet’s south pole. However, this appearance is deceiving – the “snow” is actually carbon dioxide ice, which forms a 26-foot-thick (8-meter-thick) layer year-round.
The darker areas seen in the images are layers of dust that have fallen on top of the ice, and these dust deposits can be found deep beneath the ice. The seasonal process brings some of this dust to the surface, creating the illusion of snow.
NASA’s Mars Reconnaissance Orbiter also captured images of winter frost lining the sides of dunes on Mars, which helps prevent erosion by keeping the dust in place until the thawing season in spring.
The Martian atmosphere plays a crucial role in shaping its landscape. As sunlight warms the carbon dioxide ice in the summer, it causes pockets of trapped gas to form within the ice. Eventually, this pressure builds enough to create a gas eruption that shoots dark dust into the air. The wind then carries this dust into swirling patterns.
While these images may appear like a beautiful winter scene, they are actually a dynamic summer scene on Mars, where gas jets spew dust across the surface.
Source: https://www.space.com/the-universe/mars/mars-orbiters-witness-a-winter-wonderland-on-the-red-planet-photos