Photo: NASA/JPL/UArizona
Although most of the times far less spectacular in size and manifestation than the ones occurring on Earth, natural processes do take place on now-dead Mars. And one of the most common such processes is the sublimation of carbon dioxide ice.
Carbon dioxide is one of the dominant gases that make up the Martian atmosphere. It has a concentration of 96 percent, far greater than what we find in Earth’s atmosphere, and yes, when it’s really, really cold (and Mars often gets chilly), it turns into the so-called dry ice.
The vast quantities of the frozen substance come together during winter in what is called seasonal polar caps, that place themselves over the sandy surface of the planet. When the temperatures rise during spring, the caps melt, but in a much more spectacular fashion than here on our home planet.
From time to time, the Sun’s hot beams of light happen to go through to the base of this ice, heating the sand beneath. This sand is arranged according to NASA in dark dunes, which, when heated, help transform the carbon dioxide ice from a solid directly to a gas in a process called sublimation.
Trapped under the surface, the gas breaks through the ice from time to time, bringing with it the dark sand and smudging it in plain view, cascading down the surface of the dunes.
It is the effect of such a process that we are treated to in this here color-enhanced image, captured by the HiRISE camera from an altitude of 318 km (197 miles) back in 2010. It’s a location just one kilometer across (0.6 miles) on the planet, identified only by its coordinates, one that because of all the dark stains visible over the white-ish surface kind of looks like it’s been smudged by running mascara.
The vast quantities of the frozen substance come together during winter in what is called seasonal polar caps, that place themselves over the sandy surface of the planet. When the temperatures rise during spring, the caps melt, but in a much more spectacular fashion than here on our home planet.
From time to time, the Sun’s hot beams of light happen to go through to the base of this ice, heating the sand beneath. This sand is arranged according to NASA in dark dunes, which, when heated, help transform the carbon dioxide ice from a solid directly to a gas in a process called sublimation.
Trapped under the surface, the gas breaks through the ice from time to time, bringing with it the dark sand and smudging it in plain view, cascading down the surface of the dunes.
It is the effect of such a process that we are treated to in this here color-enhanced image, captured by the HiRISE camera from an altitude of 318 km (197 miles) back in 2010. It’s a location just one kilometer across (0.6 miles) on the planet, identified only by its coordinates, one that because of all the dark stains visible over the white-ish surface kind of looks like it’s been smudged by running mascara.
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