Voyager 1

  • Launched on September 5, 1977
  • Surveyed the Jupiter and Saturn systems
  • First spacecraft to reach interstellar space
  • RTGs still operating
  • Currently exploring beyond our solar system

Voyager 2

  • Launched on August 20, 1977
  • Only spacecraft to visit Jupiter, Saturn, Uranus and Neptune
  • RTGs still operating
  • Currently exploring the edge of the solar system

Each powered by:

  • 3 Multi-Hundred Watt (MHW) RTGs stacked in a series on a boom, producing about 158 We each, at launch.
Voyager 2 is the only spacecraft to have visited all four giant planets, and the only one to have flown past distant Uranus and Neptune.
Voyager 2 is the only spacecraft to obtain this unique view from beyond the orbit of Neptune and its large Moon, Triton. Credit: NASA/JPL-Caltech

As the electrical power decreases, power loads on the spacecraft must be turned off in order to avoid having demand exceed supply. As loads are turned off, some spacecraft capabilities are eliminated.

Voyager Goals & Accomplishments

Voyager 1 and 2 were designed to take advantage of a rare planetary alignment to explore the outer solar system. Voyager 1 targeted Jupiter and Saturn before continuing on to chart the far edges of our solar system. Voyager 2 targeted Jupiter, Saturn, Uranus and Neptune before joining its sister probe on their interstellar mission.

Voyager proved to be one of the greatest missions of discovery in history. Among their many revelations about the solar system are:

  • Rings around Jupiter
  • Volcanoes on Jupiter's moon Io
  • Moons of Saturn that shepherd its rings
  • New moons around Uranus and Neptune
  • Geysers of liquid nitrogen on Neptune's moon Triton
  • Revealed and crossed the farthest boundary of our solar system

Voyager 2 is the only spacecraft to study all four of the solar system's giant planets at close range. The Voyagers are now exploring the outermost reaches of our sun's influence, where the solar wind mixes with the interstellar wind of our galaxy. Their long-lived power source has enabled these explorers to continue teaching us about our solar system for more than years after they left earth.

Mission Elapsed Time

Voyager 1

September 5, 1977

Voyager 2

August 20, 1977