CAPE CANAVERAL, Fl. (WHTM) — It launched second but reached its target first.

On September 5, 1977, the Voyager 1 spacecraft blasted off from Cape Canaveral, Florida, on its way to planet Jupiter and points beyond. Voyager 2 launched a few weeks earlier, on August 20, 1977.

Get daily news, weather, breaking news, and alerts straight to your inbox! Sign up for the abc27 newsletters here

The Voyager mission took advantage of a rare geometric arrangement of Jupiter, Saturn, Uranus, and Neptune in the late 1970s and the 1980s, an alignment that only takes place about every 185 years. This allowed the crafts to make a four-planet “grand tour”, using the gravity of each planet to “slingshot” the probe to the next, without large, heavy propulsion systems. Because of the position of Jupiter in relation to Earth at the time of the launches, Voyager 1 would actually reach the giant planet four months before Voyager 2.

  • Voyager1, aboard Titan/Centaur-6 lifts off on September 5, 1977, joiniing its sister spacecraft, Voyager 2, on a mission to the outer planets. (NASA)
  • Artist conception of Voyager in space (NASA)
  • On September 18, 1977, Voyager 1 took this picture of a crescent-shaped Earth and Moon together- the first of its kind ever taken by a spacecraft. (NASA)
  • NASA’s Voyager 1 took this picture of the planet Jupiter on Saturday, Jan. 6, 1979
  • The close pass of Jupiter, showing the Great Red Spot (NASA) Image taken on March 5, 1979 This image was re-processed on November 6, 1998 and re-recorded to film on the MDA film recorder, MRPS ID# 93779, from which this file was scanned. Original vidicon image size is 800 lines with 800 pixels per line.
  • Moon Europa. This image was one of the first hints that Europa was a frozen planet with an interior ocean. (NASA/JPL)
  • Voyager 1 image of Io showing active plume of volcano Loki on horizon. Io is the most volcanically active body in the Solar System.(NASA/JPL/USGS)
  • Voyager 1 view of Saturn, taken after its close pass of the planet. (NASA/JPL)
  • Layers of haze covering Saturn’s moon Titan are seen in this image taken by Voyager 1 on Nov. 12, 1980 at a range of 13,700 miles (22,000 kilometers). (NASA)
  • Each voyager carries a 12-inch gold-plated copper disccontaining greetings in 60 languages, eamples of music from around the world, and “sounds of Earth”. (NASA)

Voyager 1’s observations of Jupiter started on January 6, 1979, and it made its closest approach of 216,837 miles from the planet’s center on March 5. By the time the spacecraft finished its flyby on April 13, 1979, it had returned 19,000 images of the giant planet and many of its satellites, most notably the moons Io, Europa, Ganymede, and Callisto. In addition, Voyager took readings on Jupiter’s atmosphere and magnetic field.

Then it was on to Saturn. Observations of that planet started on August 22, 1980. On November 11 the flyby began, with Voyager passing the Moons Titan and Thetis before making its closest approach to Saturn, then passing Mimas, Enceladus, Rhea, and Hyperion.

And with that, Voyager 1’s exploration of the planets was over. In order to fly past Titan, the trajectory of the spacecraft had to take it below Saturn’s south pole and away from the other outer planets. It would fall to Voyager 2 to get our first close-up shots of Uranus and Neptune.

Both Voyagers continue their journeys into interstellar space, and both of them continue to send back information about the boundary between the inner solar system and the rest of the galaxy. How much longer they will be able to perform is open to question; the power levels in the craft are slowly dropping, and some instruments have already been shut down to conserve energy. The best estimates are they will cease to function sometime in the 2030s.

Not bad for a space mission that was only planned to last five years…