Images of snow on Mars

 Snow on Mars revealed through images of the Red Planet

A mysterious winter wonderland on Mars has been revealed, captured in stunning high-resolution images by two of the most advanced space orbiters. Mars orbiters witness a 'winter wonderland' on the Red Planet. Snow dots the Martian landscape in the images from ESA's Mars Express orbiter and NASA's Mars Reconnaissance Orbiter. The hills in Mars' Australe Scopuli region, located near the planet's south pole, are covered in carbon dioxide ice. The darker areas are layers of dust. Well, even if there's no snow where you live, at least you can enjoy these images of a "winter" wonderland on Mars. Taken by the German-built High Resolution Stereo Camera (HRSC) on the European Space Agency's (ESA) Mars Express orbiter and by NASA's NASA's Mars Reconnaissance Orbiter using its High-Resolution Imaging Science Experiment (HiRISE) camera, these images showcase what appears to be a snowy landscape in the Australe Scopuli region of Mars, near the planet's south pole. But the "snow" seen here is quite different from what we have on Earth.

Recently released images from two orbiters have revealed CO2 ice and dark dust patterns stretching across the planet’s southern region, creating a frosty illusion near the South Pole. Captured by the European Space Agency’s Mars Express and NASA’s Mars Reconnaissance Orbiter, the images show swirling white and brown textures covering the Australe Scopuli region. While the surface might appear peaceful, the phenomena behind it are anything but. What looks like frozen calm is, in reality, a dynamic and violent process caused by sunlight hitting CO₂ ice. A series of vertical bars of swirling purples, blues and greens showing various layers of dust and ice in Mars atmosphere in the images released. ESA spacecraft sees a kaleidoscope of colour in Mars' atmosphere. In fact, it's CO2 ice, and at Mars' south pole, there's 26-foot-thick (8-meter-thick) layer of it year-round. In this icy valley in the Australe Scopuli region, the dark and light bands are alternating layers of dust and ice. 

So, is it snow? Not quite. The white surface seen in the ESA and NASA images is composed of CO2 ice, not frozen water. Unlike Earth’s snow, this type of frost is colder, more fragile and doesn’t behave the same way under sunlight. “Martian snow comes in two varieties: water ice and carbon dioxide, or dry ice. Because Martian air is so thin and the temperatures so cold, water-ice snow sublimates, or becomes a gas, before it even touches the ground,” as stated by the NASA. So why does it look like there's just a dusting of "snow" in the images? Those darker areas are layers of dust that have fallen on top of the ice. The dust is typically found deep beneath the ice, but a seasonal process brings some of it to the surface. NASA's Mars Reconnaissance Orbiter also saw winter frost lining the sides of dunes on Mars. This frost can prevent erosion, NASA writes, keeping the dust that makes up the dunes in place until the thawing season in spring.

ESA’s Mars Express, equipped with a German-built High-Resolution Stereo Camera, snapped the initial images in June 2022. A few months later, NASA’s orbiter followed up with more views using its HiRISE camera. Both sets of photos focused on the Australe Scopuli region near the planet’s southern ice cap. As reported by the Economic Times, the CO₂ ice sheet here can be up to 8 meters thick and stays frozen year-round. On top of that ice lies a patchwork of dark dust, picked up and moved across the surface by subtle but powerful Martian winds. Over time, this dust becomes part of a visual signature which tells scientists when and how the ice has changed. The contrast between light and dark areas is striking, and also informative. The Martian dunes in Mars' northern hemisphere were captured from above by NASA's Mars Reconnaissance Orbiter using its High-Resolution Imaging Science Experiment (HiRISE) camera on 08 Sep, 2022.  As sunlight warms the CO2 ice on Mars' south pole in the summer, the ice begins to sublimate, or turn directly from a solid into vapour. As it does so, pockets of trapped gas form within the ice. While the surface might look like a peaceful frost-scape, it’s actually being shaped by pressurized gas jets just beneath the ice. Here’s how it works: in the Martian summer, sunlight begins warming the CO2 ice from below.

Eventually, the pressure builds enough to create a little gas eruption, which is powerful enough to shoot the dark dust found beneath the ice into the air. As the dust falls back to the surface, the wind carries it into these swirling patterns. (Side note: a similar process creates the spider-like features found on the Martian surface.) “The CO2 ice does not melt. Instead, it goes back from solid to gas directly in the atmosphere. That leads to the formation of really unique surface features,” explained Sylvain Piqueux of NASA’s Jet Propulsion Laboratory. Since the gas can’t escape right away, it builds up until it bursts through, carrying dust into the thin atmosphere before it drifts back down in twisting streaks. This process, as explained by the Space.com, is responsible for the swirling dark patterns seen in the imagery. They aren’t fixed, they change with the seasons, depending on the location and timing of the gas’s escape.

Beyond the icy plains, NASA’s orbiter spotted another surprise: a layer of seasonal frost coating the sides of sand dunes. Though it might seem like a minor detail, this thin crust actually plays a big role in stabilizing the landscape. The frost acts like a temporary glue, holding dust and loose particles in place until spring arrives. Once the temperature rises, the frost sublimates, just like the CO₂ ice, and the material underneath is released, often reshaped by wind. This subtle dynamic means Mars is home to slow, quiet processes which prevents erosion, preserve geological features and signal how even minor seasonal changes can impact terrain over time. So what looks like a beautiful pastoral winter scene in these Mars Express images is actually a dynamic summer scene, where gas jets spew dust across the surface. It's still cold outside, just a casual -193°F (-125°C).