Are three weirdly stacked stones on Mars giving hints about the history of the whole planet? The most recent picture taken by NASA’s Perseverance rover shows something uncannily Earth-like. Three stones rise above the barren ground of Mars’ surface, looking just like something humans might create by stacking up stones as some kind of landmark. What makes the picture interesting isn’t what it shows, but what it might tell us about what shaped those rocks and what the process might say about Mars’ geological past.
The image was acquired with Perseverance’s Mastcam-Z system on Sol 1,859 on May 13. At first glance, the image seems to show three individual stones stacked together. However, as with most images like this from Mars’ surface, what you see at first glance isn’t necessarily what you get. While there may be three distinct stones, what could actually be seen here is a large stone broken into layers and shaped in such a way that it looks odd to us.
This matters for Mars because, while water erosion shaped the landscapes we know from Earth, wind erosion is now doing a similar job on Mars. Research based on observations made from Curiosity’s journey across Gale Crater suggested that the winds have worked as a geological sculpting force on Mars for several hundred million to billions of years. This means that, over time, rocks were slowly abraded, cracked, and worn down in such a way that it could make them appear to look deliberately stacked. This, in turn, is important because, for all the science behind unusual stones, their study could give insight into the history of Mars.
In particular, Perseverance has been working in and around the crater named Jezero. In this part of Mars, NASA’s scientists found many different kinds of rocks that make up the crater rim. These include rocks created by impacts in the distant past and exposed due to weathering or eroded in some other way. Moreover, Jezero Crater has been giving up rocks that show evidence of past interactions with water such as those sampled in 2025, when Perseverance collected samples of rocks from the site at its highest rate since arrival on the Red Planet. This includes rocks containing serpentine minerals, the result of a reaction between certain igneous rocks and water. All of which makes it clear why an odd rock formation like the one shown here should not be ignored.
Since the first lander on Mars, space agencies have been taking pictures showing all sorts of rock formations on Mars. Some have raised questions about their origin. But the general principle remains constant odd shapes and textures always provide a clue for scientists interested in Mars’ history. They show us something unique about how certain rocks were formed, whether the stone underwent any kind of interaction with water, how much it was altered in any kind of impact event, and what happened during the era when Mars changed from a warm world with liquid water to its present state, controlled by dry winds and ice. Perseverance was specifically sent to study this history, after all.