Probes orbiting Mars capture its surface in detail. The Mars Reconnaissance Orbiter provides many images of exciting features on the red planet’s surface, such as a pyramid-shaped or happy face. According to scientists, erosion is responsible for these phenomena.

Red Planet Canyon Erosion

A high-performance HiRISE camera took the images aboard the Mars Reconnaissance Orbiter. According to this camera’s parameters, it can be easily deduced that the base of the “pyramid” has real dimensions of about 40 × 30 meters.

NASA/JPL/University of Arizona

According to the identification of images from the Candor Chasma area, this is not a building. Candor Chasma, where the pyramid formation is located, is one of the Valles Marineris system’s largest canyons. It represents the largest known system of canyons in the solar system.

It is not yet entirely clear how Candor Chasma Canyon was formed. However, it is clear from the detailed images that there were powerful forces of erosion, wind, dust, and water. In the vicinity of the “pyramid” in question, there are, in fact, many more or less similar “pyramids,” “columns,” and other formations. And it’s all more than evident that they were shaped by erosion.

Thermal Erosion at the South Pole of Mars

Happy Face Crater at the south pole of Mars is the result of thermal erosion. Erosion is caused by sublimation (conversion of a solid into a gas). During the winter, carbon dioxide freezes on the red planet and forms a thin layer of dry ice on earth. When the sun’s rays hit it, the ice melts, the liquid phase jumps over, and turns directly into steam, causing erosion on the surface.

NASA/JPL/University of Arizona

A comparison of photos from 2011 and 2020 helps scientists understand the annual cycle of deposition and polar frost removal. More extended observations provide insight into long-term climate trends on Mars.