While it may be true that in space no one can hear you scream, that doesn’t necessarily mean the universe is completely silent. Recordings released by NASA in the early '90s show just how noisy space can be if you know how to listen.

In 1977, NASA launched Voyagers 1 and 2 into the vacuum of space in hopes of studying the outer planets of our solar system. Traveling at about 30,000 miles per hour, these probes have traversed billions of miles since their launch, all while sending home vast amounts of information and images of some of our more distant neighbors, including Jupiter, Saturn, Neptune, and Uranus. On August 25, 2012, Voyager 1 became the first human-made object to leave our solar system, and it still manages to send back vital information in messages that take over 17 hours to reach Earth.

Voyager 1 may have to wait about another 40,000 years to approach another star, but that may be a relief to the probe, because our neighbors never shut up. There may be no mechanical noise—sound that requires a medium such as a solid, liquid, or gas to resonate through—in space, but electromagnetic waves have no problem traveling through a vacuum. As they passed by the outer planets, Voyagers 1 and 2 recorded this wave data as solar wind clashed with the planets’ magnetospheres. The probes also managed to listen in on atmospheric radio waves, charged particle interactions, and even some particle emissions from places like Saturn’s rings, then relay all of this data back home.

Electromagnetic waves can’t be heard in their raw form, but that doesn’t mean they can’t be converted into something audible. Just as radio waves can be translated into the sound of morning FM talk show hosts, the Voyager data streams can be converted into audio, thereby letting humans listen in on interplanetary conversations. And, as it turns out, these conversations are riveting. 

In 1992, NASA released a series of these recordings entitled Symphonies of the Planets. The tracks are beautifully haunting in a way that rivals anything experimental electronic artists make. The collection’s echoing siren sounds manage to give the listener a sense of just how vast and complex our universe is, as well as how amazing an achievement the Voyagers are. Unfortunately, due to some cosmic injustice, the albums are no longer in print, but just like the electromagnetic waves, there are ways to still listen to them. Copies now exist on YouTube and streaming services like Spotify. Go ahead and give them a listen, and try not to get misty-eyed while hearing what the Voyagers heard as they hurtled onward into a vast, quiet universe. Well, relatively quiet.

See also: What Does Space Smell Like?