Are There Really 'Spiders' on Mars? Uncovering the Mystery of Martian Geysers

The European Space Agency's Mars Express mission is capturing something spectacular on the Red Planet: the curious phenomena known as 'Martian spiders.' Despite their name, these features are not actual arachnids, but rather intricate patterns on Mars' surface that tell a story of seasonal transformation.

Located primarily in the southern polar region of Mars, these 'spiders' emerge in the Martian spring when the sun warms the ice layers composed of carbon dioxide, also known as dry ice. This process causes the ice at the bottom to sublimate — that is, transform from a solid directly into gas. The gas builds up pressure until it bursts through the ice layer, carrying dust and dark material upwards through cracks and crevices, and creating plumes that resemble geysers.

As the dust settles back down, it forms dark spots ranging from 45 meters to 1 kilometer across, surrounded by radial patterns that starkly resemble the legs of a spider. These unique formations are not only fascinating geological features but also provide clues about Martian atmospheric conditions and seasonal changes.

Adding to the intrigue, another of ESA’s Mars explorers, the ExoMars Trace Gas Orbiter, has provided clear images of these tendril-like patterns. Although these images were taken from a different location, they show similar dark spots and 'spider' patterns, offering a more detailed look at the phenomenon from above.

These formations predominantly appear over the Martian landscape known as Inca City, a region named for its ridge patterns that resemble the ancient Incan ruins on Earth. Officially called Angustus Labyrinthus, this area was first identified by NASA's Mariner 9 probe in 1972 and continues to be a point of interest due to its unique geological formations and the mysterious origins of its landscape.

Scientists speculate that Inca City could be the remnants of sand dunes that solidified over time or perhaps a result of magma or sand moving through fractured Martian rock. The area also features glacier-related structures known as eskers and sits within a large crater, suggesting an impact origin which has shaped the surrounding landscape dramatically.

The Mars Express mission has been a significant source of information, enhancing our understanding of Mars. Over two decades, it has mapped the planet's minerals, studied the atmosphere, and explored beneath the crust, revealing the dynamics of the Martian environment. From observing wind-sculpted features to analyzing ancient lava pools and river channels, the mission paints a comprehensive picture of Mars as a planet with a complex and active geological history.

As we continue to uncover the secrets of these Martian 'spiders,' each finding adds a piece to the puzzle of Mars' environmental and geological complexities. These discoveries not only provide insights into Mars’ past but also help prepare for future explorations, possibly even human missions, as we seek to learn more about our fascinating planetary neighbor.

Credit: European Space Agency

Reference URL: European Space Agency - Mars Exploration