(spoiler alert for both movie and book)
If I recall correctly, the destination planet for the astronauts in 2001 the book was Saturn. This added an intriguing twist to the end of the movie: it’s realized that Saturn’s rings were deliberately created to highlight the planets, so that humans would know to look here for the monolith.
The movie has no such mention; the mission is to Jupiter, though no real explanation is given of why.
Am I remembering the book correctly? Anyone know why the change happened?