Space is creepy. The universe is crawling with black holes, neutron stars, meteorites and asteroids that can smash into you at any second, and a planet that’s like the most immense total blackout ever. It’s also got the soundtrack to go with it.
NASA has just compiled one heck of an unsettling Halloween soundtrack, enough to make those eerie oooooooooEEEEEEoooooo sounds (that thing you hear when you walk by a motion-activated ghost) and scream recordings sound like easy listening. The results are more likely to give you nightmares than Parnormal Witness. Unlike playlists of shrieking murder victims that you know are just actors who are very alive, what’s really scary about these sounds is that they’re real.
Planets often make spooky sounds—think phantom whistles of helium and planets howling like werewolves—and spacecraft that is equipped to capture radio emissions transmit them back to Earth. When NASA spacecraft Juno dared to venture into Jupiter’s massive magnetic field, it recorded a bow shock which sounds like something that belongs on the soundtrack of a sci-fi horror movie. The upstream plasma oscillations sound scary enough before the spacecraft crosses over into the menacing magnetosphere. Oh, and this recording lasted for two hours, so it’s pretty much an instant soundtrack for your Halloween party.
The only way to describe whistler-mode plasma waves, which is what happens when electrical discharge from lightning that strikes Earth escapes the atmosphere and bounces irregularly along our planet’s magnetic field lines, is like the pew-pew-pew of alien blasters in a video game. The higher the frequency, the faster the discharge travels, which gives it that characteristic falling pitch that sounds almost digital.
When electrons are bumped towards Earth’s night side, you get the ghostly harmony otherwise known as chorus plasma waves. None of these are more ominous than a plasmaspheric hiss. When whistler-mode waves float through the plasmasphere, the result is something like car radio static that gets louder and louder until the car stops and something like Mothman smashes the windshield.
Saturn’s radio emissions, picked up by Cassini, are more atmospheric. The resulting noises were not unlike wind blowing through skeletal trees on a moonless night.
When the spacecraft Galileo made its first flyby of Jupiter’s moon Ganymde in 1996, scientists converted the radio signals received from the craft into sound waves in a process called data sonification. You’d expect to hear this kind of background noise as you enter a long-abandoned spaceship and hold your breath that you escape both unscathed and without incubating a chestburster.
The monster mash isn’t just reserved for planets and moons and rebel electrons. Comets make weird noises, too. What sounds like a staticky machine gun from a vintage horror film is actually frozen balls of dust that bombarded the protective shield of NASA’s Stardust-NExT spacecraft as it zoomed through the cloud of debris shrouding comet Tempel 1.
So which one of these eerie emissions is going to keep you awake tonight?