As of 2006, spacecraft originating on Earth can reach Jupiter in 13 months. The effective time that it takes to send objects from Earth to Jupiter continues to decrease with technological improvements.
The amount of time necessary to reach Jupiter varies depending where the planets are in their orbit. In 1989, the Galileo spacecraft took six years to travel between the two planets. An early mission by Voyager 1, launched at a more favorable time in the planets' orbits, took only two years. Launched in 2011, scientists expect the spacecraft Juno to reach Jupiter in five years. While seen as theoretically impossible, a spacecraft travelling at the speed of light would reach Jupiter in 43 minutes.