Voyager 2 carries a Golden Record

The launch from Kapustin Yar illustrates international cooperation in the early Indian space program.

The spacecraft took its name from the mathematician and astronomer whose work was studied in the earlier astronomy batch.

Despite its number, Voyager 2 departed before Voyager 1, beginning its journey to the outer planets.

Voyager 2 took a path that would later permit encounters with Jupiter, Saturn, Uranus and Neptune.

The spacecraft carried cameras and instruments to study planets, moons and their environments.

The second Voyager launch used a trajectory that overtook Voyager 2 on the way to Jupiter.

Voyager 1 began a mission designed to return images and measurements of distant giant planets.

Its record presented sounds and images from Earth to any future finders of the spacecraft.

The 5 September launch completed the pair’s departure for outer-planet exploration.

Researchers compared thousands of dated observations with modern orbital calculations to study long-term changes in Earth's rotation.