A Man, a Plan, a Canal—Mars!

A wealthy amateur astronomer in the early 20th century convinced the world that Mars was crisscrossed by canals built by an advanced civilization. Using his self-funded observatory, he published detailed maps and theories that captured the public imagination, fueling science fiction and doomsday speculation. The idea persisted for decades after professional astronomers debunked it—a cautionary tale of how personal conviction and resources can drown out skeptical evidence.