Twin Voyager missions are underway

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

The probe’s record carried images and sounds selected to represent life and culture on Earth.

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.

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

A mismatch between predicted and recorded eclipse paths reveals accumulated changes in the length of the day.

Records reaching back many centuries give modern science a time span impossible to reproduce with recent instruments alone.

Chinese textual expertise and modern celestial mechanics together create evidence neither discipline could produce independently.

The telescope lifted off aboard space shuttle Discovery for an orbit above Earth’s atmosphere.