Seen here is a full-scale model of one of the twin Voyager spacecraft, which was sent to explore the giant outer planets in our
solar system. Voyager 2 was launched August 20, 1977 followed by the launch of Voyager 1 sixteen days later. Both spacecraft visited Jupiter and Saturn, with Voyager 2 continuing its journey to Uranus and Neptune. In spring 1990, Voyager 2 transmitted images looking back across the span of the entire solar system. Both Voyagers continue to explore interstellar space.
                                                                               
                                                                              Testing

Each of the two Voyagers was a self-contained system that carried its own power generation system, propulsion system,
communication equipment, and scientific instruments. Seen here are the 3.7 m (12.1 ft) high-gain antenna dish and the 10-sided
main body that houses the command and control subsystems. The segmented black cylinder on the right side of the spacecraft is Voyager's power supply. Notice the size of the technician working on the model at the lower right.
                                                                          
                                                                            Simulation

Part of the preflight testing requirements for the Voyager spacecraft included space simulations. Shown here is one of the
Voyagers in a flight simulator. The simulator is vacuum sealed and cooled with liquid nitrogen. Beneath the floor are 37 arc
lamps that shine through the floor and onto a mirror on the ceiling. The mirror and lights together are designed to simulate solar
thermal radiation. With the simulator, scientists are able to test the spacecraft's performance in realistic situations.
                                                                              
                                                                Preparing for Launch

A nose cone that contained one of the Voyager spacecraft is seen here as it is mounted on top of a Titan III/Centaur launch
vehicle.
                                                                          
                                                                 Launch of Voyager 2

Voyager 2 was launched August 20, 1977, onboard a Titan III/ Centaur rocket. Although Voyager 2 was launched 16 days
before Voyager 1, it arrived at Jupiter four months later than its sister craft. The initial mission plan for Voyager 2 specified visits only to Jupiter and Saturn. The plan was augmented in 1981 to include a visit to Uranus, and again in 1985 to include a visit to
Neptune. Voyager 2 completed both of those missions and is currently performing scientific experiments in interstellar space.
                                                                             
                                                                 Launch of Voyager 1

On September 5, 1977, Voyager 1 was launched from Kennedy Space Center at Cape Canaveral, Florida. Although Voyager
1 left Earth 16 days after Voyager 2, its faster flight path allowed it to pass the slower craft and arrive at Jupiter more than four
months ahead of Voyager 2. The launch vehicle, shown here, is a Titan III E/ Centaur rocket, which stands nearly 50 m (164 ft) high and weighs almost 635,000 kg (1.4 million lb).