Humans have been seeing strange things on the surface of Mars for centuries. Perhaps it’s because, other than Earth, Mars is the closest thing in the solar system to a habitable planet, or perhaps it’s simply because it’s close enough to get a pretty good look at.
Either way, Earthlings have been fooled time and again by the rocky Martian surface and their own psychology. People have at various times reported finding everything from canals to spooky humanoid faces to alien Martian bases on the surface of the Red Planet — though each sighting has been thoroughly debunked.
In this vast universe, are Earthlings just desperate for next-door neighbors to play with? Looking back over the long history of Martian illusions (and human delusions), it certainly seems so.
Land and Sea
In 1784, Sir William Herschel, a famous British astronomer, wrote that dark areas on Mars were oceans and lighter areas were land. He speculated that Mars was inhabited by intelligent beings who “probably enjoy a situation similar to our own,” according to NASA. Herschel’s theory prevailed for a century, with other astronomers claiming that vegetation could even be observed in the lighter-colored regions that were taken to be land. Fortunately for Herschel, his other contributions to astronomy — which have earned him the honor of being the namesake of two powerful observatories — were great enough to keep his theories on Martians near the bottom of his biography.