2001: A Space Odyssey (soundtrack) used is Ligeti's "Lux Aeterna" and an electronically altered form of his "Aventures", the last of which was so used without Ligeti's permission and is not listed in the film's credits. Since the film, "Also sprach Zarathustra" has been used in many other contexts. It was used by the BBC and by CTV in Canada as the introductory theme music for their television coverage of the Apollo space missions, as well as stage entrance music for multiple acts including Elvis Presley late in his career. Jazz and rock variants of the theme have also been composed, the most well known
2001: A Space Odyssey (film) science-fiction films of the time, Kubrick used Homers "The Odyssey" as inspiration for the title. Kubrick said, "It occurred to us that for the Greeks the vast stretches of the sea must have had the same sort of mystery and remoteness that space has for our generation." Kubrick and Clarke planned to develop the first, free of the constraints of film, and then write the screenplay. They planned the writing credits to be "Screenplay by Stanley Kubrick and Arthur C. Clarke, based on a novel by Arthur C. Clarke and Stanley Kubrick" to reflect their preeminence in their respective fields.