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 (soundtrack) It is subsequently heard when an ape first learns to use a tool, and when Bowman is transformed into the Star-Child at the end of the film. "Zarathustra" thus acts as a bookend for the beginning and end of the film, and as a motif signifying evolutionary transformations, first from ape to man, then from man to Star-Child. This piece was originally inspired by the philosopher Nietzsche's book of the same name which alludes briefly to the relationship of ape to man and man to Superman. "The Blue Danube" appears in two intricate and extended space travel sequences as well