The Voyager Golden Record, 1977

Voyager spacecraft launched in 1977 carry a golden record—a message in sound, music, and images from Earth, traveling beyond our solar system into the cosmic unknown.

In 1977, NASA launched two spacecraft about the size of a compact car and gave them a task that was pure engineering: to visit the giant planets while a rare alignment made the route possible. Voyager 2 left Earth on August 20, and Voyager 1 followed on September 5. Their flight paths would transform planetary science, but bolted to each spacecraft was something with no practical use for navigation, power, or data: a gold-plated copper phonograph record.

The Voyager Golden Record was assembled by a team led by astronomer Carl Sagan at Cornell University. The group included Ann Druyan, Frank Drake, Jon Lomberg, Timothy Ferris, and others who had only weeks to decide how Earth should introduce itself. It was not a realistic attempt to start a conversation. It was closer to a time capsule, a tiny museum of one planet attached to machines expected to outlive their makers.

The record carries greetings in fifty-five languages, ranging from Akkadian, once spoken in ancient Mesopotamia, to English, Arabic, Mandarin, French, Spanish, Hindi, and many others. The English greeting was spoken by Nick Sagan, Carl Sagan’s young son: a simple hello from the children of planet Earth. The package also included printed messages from President Jimmy Carter and United Nations Secretary-General Kurt Waldheim, formal voices from the political world of the late 1970s.

Then there are the sounds. The team made an audio postcard of Earth: wind, thunder, surf, rain, birds, frogs, crickets, chimpanzees, elephants, and the eerie calls of whales. Human life is there too: footsteps, laughter, a heartbeat, a mother and child, tools, a train, a tractor, Morse code, and a rocket launch. It is not a textbook. It is an impression: a wet, noisy, living planet where animals call, machines run, and people build, breathe, and laugh.

The music lasts about ninety minutes, and every selection meant excluding thousands more. Bach is included, among others, as are Beethoven, Mozart, Stravinsky, and a Georgian choral song. The record also carries music from Peru, Java, Japan, India, China, Senegal, Bulgaria, and the Navajo Nation. From the United States came Blind Willie Johnson’s “Dark Was the Night, Cold Was the Ground” and Chuck Berry’s “Johnny B. Goode.” Some people wondered whether rock and roll was too ordinary for the stars. In hindsight, that ordinary human energy may be exactly why it belongs.

The record also contains images: scientific diagrams, human anatomy, plants, animals, landscapes, buildings, roads, vehicles, and people eating, working, and learning. NASA usually describes the set as 116 images. They were not stored as modern digital files, but as analog video information. A finder would first have to understand how to play the record, and then how to turn the signal back into pictures.

That is why the cover matters so much. Etched onto it are instructions meant for a mind that knows physics but not any human language. The diagrams show how to place the stylus, how fast the record should turn, and how to decode the images. The basic unit of time is defined by a transition in neutral hydrogen, the most common element in the universe. In other words, the cover avoids seconds, inches, centimeters, and all local customs. It tries to build from nature itself.

The most famous symbol is the pulsar map, an idea associated with Frank Drake and also used on the earlier Pioneer plaques. Pulsars are dense remnants of dead stars, spinning rapidly and sending out beams of radio energy like cosmic lighthouses. The map gives the Sun’s position relative to fourteen pulsars and lists their pulse periods in binary notation. Because pulsars gradually slow down, the pattern could, in principle, work as both a map and a date stamp. That remains a hypothesis. It assumes the map survives, the pulsars are identifiable, and the finder thinks enough like a physicist to solve the puzzle.

Voyager 1 flew past Jupiter in 1979 and Saturn in 1980. After Saturn, gravity sent it upward out of the plane of the planets and toward interstellar space. On August 25, 2012, it crossed the heliopause, the boundary where the solar wind gives way to the environment between the stars. It became the first known human-made object to enter interstellar space. Voyager 2 crossed the same boundary in 2018, after visiting Jupiter, Saturn, Uranus, and Neptune.

Today, Voyager 1 is more than twenty-five billion kilometers, or nearly sixteen billion miles, from Earth, moving outward at about seventeen kilometers per second. A radio signal now takes more than twenty-three hours to reach it, and its reply needs the same long journey back. Mission control does not chat with Voyager. It sends a command and waits almost two days to learn what happened.

Both Voyagers are powered by radioisotope thermoelectric generators, which turn heat from decaying plutonium into electricity. That power has been fading for decades. Engineers have shut down heaters and instruments one by one to keep the spacecraft alive. NASA expects the remaining science operations to decline through the late 2020s and perhaps into the early 2030s, depending on the aging hardware.

After that, the spacecraft will fall silent, but they will not stop. The Golden Records are not aimed at any nearby star, and space is almost unimaginably empty. Unless dust or a collision destroys them, they may drift for hundreds of millions of years: two small records carrying greetings, whale song, Bach, Berry, diagrams, and a map home.