Percival Lowell spent years mapping spoke-like features on Venus that turned out to be the blood vessels of his own retina, and he popularized a network of Martian canals that never existed. Yet the same man pioneered high-altitude observatory placement and set in motion the discovery of Pluto. This episode follows the Boston Brahmin from a Harvard mathematics degree and six years running the family cotton mills, through a decade in Korea and Japan writing about psychology and imagination, to the founding of Lowell Observatory in Flagstaff, Arizona in 1893.

We explain why atmospheric seeing matters more than city lights, how a mistranslation of Schiaparelli's canali primed Lowell to see engineered canals, and how a stopped-down 24-inch refractor turned into an ophthalmoscope. We then cover his final decade searching for Planet X through gra ...