|Voyager's golden record cover.|
Voyager 1 and 2 were designed not only to provide scientific information about our solar system, but to act as ambassadors of the planet Earth. In this latter aspect, they are essentially greeting cards from the human race.
Nine months before the Voyagers were scheduled for launch, Carl Sagan was given the job of deciding what to put inside the spacecraft -- the collection of sights and sounds that might one day introduce the human race to aliens. They were pressed into the record you see above. And yes, it was covered in gold.
The article outlines Sagan's vision for the project and discusses some of the choices he made. One day, an intelligent alien civilization may encounter the Voyagers and learn of our existence -- and a bit about who we are (or were, if we have gone extinct by that time or evolved into something so different that we can't even imagine it now).
So what do you put aboard a small spacecraft to tell the tale of Earth and its people to a group of aliens? Read the story. It's marvelous, and not long. I miss Carl Sagan. No one has come close to replacing his enormous vision, intellect and kindness. We lost a great one when he died. But at this very moment, the Voyager spacecraft are leaving our solar system and heading into the universe beyond. I like to think that a few million years from now, an alien civilization will come to come to know and appreciate us -- and Sagan, by extension -- when they discover this time capsule. It's a fitting legacy for such a grand old man of science.