From our vantage point on Earth, humanity has only ever seen, and will always see, one side of the moon. Our planet’s gray companion rotates on its axis at the same speed that it orbits Earth, a celestial arrangement that keeps the same side perpetually turned toward us.
The landscape has remained largely unchanged for hundreds of millions of years, but we human beings have managed to imagine all kinds of patterns in its craters, where molten lava once flowed, carved into existence by the cosmic collisions that shaped our home in the cosmos. We have turned the moon into a canvas, etching fables and fantasies across its surface in an attempt to make some earthly sense out of its mysticism.
A plethora of interpretations have emerged throughout human history. For some, the lunar features formed the silhouette of a rabbit. For others, the eyes and mouth of a human face. Or a woman and her child. Or an old man lugging firewood, perhaps with a small dog trailing after him. The interpretations arose in a myriad of disparate communities, but they share the same origin: our minds.
The human brain is built to discern familiar images and patterns in places where none exist, a psychological phenomenon known as pareidolia. “It happens because the brain is doing what it’s designed to do, which is to make inferences about what’s in the world based on very limited information,” says Pawan Sinha, a vision and computational-neuroscience professor at MIT. “If I were to see you at a distance of a hundred feet, the image of your face on my retina is going to be very small. But even using just those handful of pixels, the brain has to infer who this person might be.”