On 12 December 2022, an orbiter passing 251 kilometers (156 miles) above the southern highlands of Mars photographed a hill. It was one of tens of thousands of images taken by NASA’s Mars Reconnaissance Orbiter HiRISE camera since 2006, and it should have been unremarkable. Instead, something appeared to be looking back.
Two dark, round pits sat like eyes. Between them, a pale ridge tapered down like a snout. A near-perfect circular crack ringed the whole formation, giving it the outline of a head. Together, the features looked almost comically like an adorable little bear.
The Geological Explanation
Alfred McEwen, the University of Arizona planetary scientist who leads the HiRISE camera team, offered a more mundane explanation in 2023. “There’s a hill with a V-shaped collapse structure (the nose), two craters (the eyes), and a circular fracture pattern (the head),” he said.
Each feature has an ordinary geological origin. McEwen suspects the circular fracture could be what remains after loose material settled on top of a buried, long-since-filled impact crater. The ‘nose’ might be a volcanic or mud vent, with the surrounding V-shape marking where lava or mud once flowed out.
Why We See a Bear
The tendency to see a sweet little bear looking back is known as pareidolia—the same wiring that turns a car’s headlights into a startled face or a water stain into a religious icon. Human brains have evolved to spot faces quickly, in bad light, from a distance. This might be because, for most of our history, recognizing ‘that’s a face’ a half-second sooner than the next primate could have been the difference between spotting a threat and missing it. The tradeoff is a pattern-recognition system so trigger-happy it finds faces everywhere—including in a grainy orbital of Martian rock.
Other Faces on Mars
It’s not the first time something has looked back at us from Mars. In 1976, NASA’s Viking 1 orbiter photographed a mesa in Mars’ Cydonia region that, at low resolution, looked eerily like a carved human face staring up at space. Higher-resolution images from later orbiters, HiRISE included, quietly ended the argument: it was a mesa—a large, unremarkable rock formation that happened to catch the light a certain way.
A completely different Martian smiley turned up much more recently, and for reasons that have nothing to do with its expression. In August 2024, scientists working with the European Space Agency’s Trace Gas Orbiter were cataloging chloride salt deposits in a region called Terra Sirenum when they came across one shaped like a smiley face—a ring of dried salt with two small craters sitting where eyes would go.
The Scientific Value of Salt Deposits
The salt itself is the interesting part. It’s what’s left behind after shallow ponds or lakes evaporated, sometime during Mars’ wetter past, letting dissolved minerals concentrate and crystallize. Salty water like that can stay liquid at temperatures down to around -40 °C, which would freeze plain water solid. This is exactly the kind of extreme, long-lasting brine where life could plausibly have hung on the longest as Mars dried out. That makes deposits like this one genuine targets for future missions hunting for biosignatures, grin or no grin.
More recently, we’ve also seen a jellyfish on Mars (that one turned out to be a cosmic ray striking the camera’s sensor), weird pits, a human bone, and mushrooms. Most of those have ordinary explanations by now—though as of this week, scientists still aren’t sure what carved the pits. But we’re continuously discovering cool things about the red planet itself. Even if it doesn’t have any bears on it.
