A grainy black shape floating above Earth, captioned as a 13,000 year old alien spacecraft that NASA is hiding. This episode dissects the Black Knight satellite legend using the framework of Martina Redpath at Armagh Planetarium, who called it a stew of unrelated events stripped of context. The hosts trace the ingredients back to Nikola Tesla's 1899 rhythmic radio signals in Colorado Springs, which science writer Brian Dunning attributes to pulsars not identified until 1968, and to Jorgen Hals's 1928 long delayed echoes in Oslo, now understood as radio waves trapped in ionospheric plasma ducts.

From there the episode follows the Cold War additions: Donald Keyhoe's 1954 mystery satellite claims made during a book promotion tour, the February 1960 Navy radar detection of a dark polar-orbit object that turned out to be a fragment of the Discov ...