The Day We Sent a Message to Aliens

The idea began with two NASA spacecrafts, Voyager 1 and Voyager 2. The original purpose of the Voyager mission wasn’t to talk to aliens. It was to collect scientific data about the outer solar system and send it back to Earth.

The Voyagers launched into space in 1977, and since then, they’ve had quite an adventure. They’ve snapped the only close-up photos of Uranus and Neptune in existence. They’ve observed Jupiter’s Great Red Spot, a violent windstorm twice the size of Earth. And they’ve beamed back invaluable data about our solar system.

About five years from now, though, the Voyagers will run out of power. After that, the spacecrafts will float aimlessly, drifting through the galaxy forever.

Back in the 1970s, NASA knew this would happen. And that got a NASA astronomer named Carl Sagan thinking: If the Voyagers were going to stay in deep space forever, wasn’t it possible that one day, another life-form might find them? In which case, Sagan wondered, could the Voyagers be our chance to communicate with aliens?

Sagan and a few colleagues wanted to attach a special message about Earth to each spacecraft. They pitched the idea to NASA, and NASA agreed.

Sagan assembled a team of scientists, writers, artists, music producers, and other experts. Their job was to figure out exactly what the message should say about humanity. They spent months poring over photos and listening to music. They wanted to show a variety of cultures, as well as different environments. They also had to be careful. They didn’t want to give aliens the wrong idea about our intentions, so they made sure not to include any images of war or crime.

The message came to be known as the Golden Record. It is a collection of sounds and images that the team encoded on a gold-plated copper disk. Two copies were made, one for each Voyager.

The Golden Record is a fascinating portrait of our world. Some images depict basic human functions: a woman eating ice cream, a man drinking water, the silhouette of a pregnant woman. Others show feats of human engineering: a train, an airplane, the Taj Mahal. Still others capture the natural features of our planet: a sequoia tree, a rocky shoreline, a tropical island.

The Golden Record also includes a 12-minute compilation of sounds such as thunder, a crying baby, a chimpanzee, and the hum of a car’s engine. Greetings in 55 languages and a map showing the location of our solar system are part of the message too.

But it is music that makes up most of the Golden Record. There are songs from all over the world: classical music from Europe, drum and pipe music from Peru, and rock ’n’ roll from America. Perhaps the record’s creators thought music could explain more to aliens about humanity than words and images ever could. 

It’s been more than 42 years since the Voyagers left our planet. The spacecrafts are now some 11 billion miles from Earth. That’s farther than any human-made object has ever traveled. They are zooming through space at a cool 35,000 miles per hour—about 20 times faster than a speeding bullet.

Maybe one day, life-forms from a distant planet will find the Golden Record drifting among the stars. If they do, what will they think of us? 

This article was originally published in the February 2020 issue.