In August 2006, the International Astronomical Union voted Pluto out of planethood. Far from the sun, tiny, and eccentric in orbit, it's a wonder Pluto has any fans. Yet during the mounting debate over Pluto's status, Americans rallied behind the extraterrestrial underdog. The year of Pluto's discovery, Disney created an irresistible pup by the same name, and, as one NASA scientist put it, Pluto was "discovered by an American for America." Pluto is entrenched in our cultural, patriotic view of the cosmos, and Neil deGrasse Tyson is on a quest to discover why.