As Mars’ northern hemisphere awakens from its frozen slumber, the Red Planet unleashes a fury of seasonal geological turbulence. The explosive arrival of spring on Mars brings violent geysers and avalanches, as well as distinctive spider-like landforms that reveal themselves when the frozen carbon dioxide has melted in the summer.
Mars’ axis of rotation is tilted at about 25 degrees, which means the Red Planet experiences four seasons just like Earth. However, a year on Mars lasts approximately 687 Earth days, making each season longer than those on our planet.
Mars, known as the Red Planet, is a rocky planet with a thin atmosphere.
Its reddish appearance is due to iron oxide in the soil.
NASA's Curiosity rover has been exploring Mars since 2012, discovering evidence of ancient lakes and rivers.
The Martian surface is divided into three main regions: the southern hemisphere's vast plains, the northern hemisphere's polar ice caps, and the Tharsis bulge, a region of volcanic activity.
Mars' atmosphere is too thin to support liquid water, making it inhospitable for human life.
The northern hemisphere of Mars has entered its new spring, with temperatures rising and frozen water and carbon dioxide changing directly from solid to gas in the thin Martian atmosphere. This results in an extremely active springtime, with all phenomena occurring explosively.
Violent Geysers and Avalanches
NASA’s Mars Reconnaissance Orbiter has captured dramatic images of the explosive arrival of spring on Mars. One image shows a 20-meter-long chunk of frozen carbon dioxide falling off a cliff, while another depicts dark, fan-shaped geysers erupting from the Martian surface.
The geysers are formed when sunlight hits carbon dioxide ice, heating the ground below and causing the ice to sublimate from solid to gas. The pressure builds up until an eruption occurs, launching carbon dioxide, sand, and dust into the atmosphere. The best time to see these geysers will be around December 2025, when spring arrives in the southern hemisphere.
Spider-Like Landforms
When the frozen carbon dioxide has melted in the summer, distinctive marks are revealed on the Martian landscape. These ‘araneidoform terrain’ formations resemble spiders when seen from space and can be over a kilometer across, with hundreds of legs. They are often found in swarms and are still not fully understood.
The Power of Spring Winds
The arrival of spring on Mars brings strong winds that move sand dunes on the Martian surface. Just like deserts on Earth, the wind action causes the dunes to shift and change shape. An image of sand dunes surrounded by frost taken by the Mars Reconnaissance Orbiter in September 2022 shows how the white stuff is frozen, but when temperatures rise, it melts, allowing the dunes to move again.
The onset of spring on Mars is indeed very active, with explosive geysers and avalanches occurring due to the rapid change from solid to gas. As Selina Diniega notes, ‘I imagine it would be very noisy, with things cracking and exploding.’
