When Star Trek hit the screens back in 1966, nobody could have guessed that it would become a cultural phenomenon that would go on to spawn scores of spin-off shows, movies, conventions and enough merchandise to fill the USS Enterprise several times over. As hard as it is now to believe, this multi-million dollar science fiction juggernaut was actually canceled after a mere three seasons. However, that was plenty of time for many fascinating stories to emerge. Here are 21 amazing facts about the original Star Trek TV series that will surprise even the most ardent Trekkies!