Jupiter was the fifth planet from the Sun. During the events of 2010: Odyssey Two, Jupiter is transformed into the new star Lucifer.
2001: A Space Odyssey Edit
Jupiter plays a different role in the novel and film versions of 2001: A Space Odyssey.
In the 2001 novel, a flyby of Jupiter is used to speed up the Discovery spacecraft on the way to Saturn.
In the 2001 film, the flyby does not occur, as the mission objective was in the proximity of Jupiter's moon Io, rather than Saturn's moon.
2010: Odyssey Two Edit
In 2010, Jupiter's density is increased by the monoliths, causing the planet to collapse upon itself and become the star Lucifer.