NASA’s Curiosity Mars rover recently observed a strange Martian feature resembling a piece of coral, though the mission team says the odd-looking object is no indication of past life on the Red Planet.
While striking in appearance, the structure isn’t evidence of ancient Martian sea life. Instead, scientists say it’s the product of natural erosion, shaped over eons by wind and water into a form that only looks biologically familiar.
The image is the latest example of how Martian landscapes can play tricks on the human mind, tapping into a psychological phenomenon known as pareidolia—the tendency to see patterns, faces, or creatures where none exist.
Detecting the Martian Coral
The image showing the unusual rock was captured on July 24, 2025, using the ChemCam instrument’s Remote Micro Imager. It was the 4,609th Martian day of the Curiosity mission, and researchers weren’t exactly surprised—similar formations have been observed before. Another coral-like rock was spotted at the same time using Curiosity’s Hand Lens Imager.
Although the discovery isn’t evidence of ancient life on the Red Planet, the rock does have a significant connection to water. The stone originally formed through interactions with water on ancient Mars, before wind erosion sculpted it into its current shape.
Geologists have developed a solid understanding of how such shapes form, based on extensive research on Earth. On early Mars, water pushed dissolved minerals into cracks within rocks. As the water evaporated, minerals were left behind and eventually hardened. These mineral deposits proved more resistant to erosion, and as Martian winds sandblasted the surrounding rock, the harder material remained—tracing the ancient cracks and forming the unusual structures.
One previous example of the same process produced a rock NASA researchers described as being reminiscent of a flower, although the eye of the beholder may be doing some of the work in that identification, showcasing a common factor in the long-running collection of strange shapes and other curiosities allegedly discovered on the Martian terrain.
Sasquatch on Mars?
Pareidolia is the human psychological tendency to perceive recognizable patterns—especially faces or figures—within visual noise. From an evolutionary standpoint, this offered a survival advantage, such as being able to pick out the shape of a predator lurking in foliage. In today’s world, saturated with images and smartphones, this once-beneficial trait can also fuel speculation and misinformation.
A light-hearted example of this came in the form of a viral image that some online users jokingly dubbed a “Sasquatch on Mars.” At first glance, the image does bear a passing resemblance to the Bigfoot figure from the famous Patterson-Gimlin film, which purportedly shows a Sasquatch striding through the woods and glancing over its shoulder. Unfortunately for proponents of more exotic theories, the Martian “Sasquatch” was nothing more than a tiny rock from a much larger panoramic image captured by NASA’s Mars Exploration Rover Spirit in 2007.
The Face on Mars
Perhaps the most famous example of Martian pareidolia is the so-called “Face on Mars,” first imaged by the Viking 1 orbiter in 1976. Early, low-resolution images showed what appeared to be a massive, eerie human-like face peering upward from a prominence located in Mars’ Cydonia region.
Led by Richard C. Hoagland, a well-known proponent of theories involving ancient civilizations on Mars, some fringe thinkers argued that the “face” was proof of intelligent life from the Red Planet’s past. Scientists largely dismissed the idea, however, attributing it to a trick of light, angle, and resolution, as later imagery of the same region revealed.
Subsequent missions to Mars in the 1990s and 2000s provided additional high-resolution data, allowing researchers to build three-dimensional models of the feature. These showed it to be nothing more than an ordinary hill. The original illusion was a result of shadows and low image quality, not the work of ancient Martian architects.
While a handful of diehard believers still allege a NASA cover-up, interest in the “Face on Mars” has waned in recent decades. Still, it remains a prime case study in pareidolia—a reminder that the human brain is wired to see meaning in randomness, especially when it comes to distant alien landscapes.
Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.