There is no sound in space (or is there?)

(You can pickup some threads with this picture here)

In space, no one can hear you scream! That's what the tagline from the film Alien taught a generation of folks. Well, at least it taught some part of a generation. Well, maybe it only slightly hinted at an idea for a minimal fraction of some part of a generation. Or something like that. 

Too many times we've gone to the movies to see yet another sci-fi adventure with spaceships blasting each other with phasers and lasers and things that go "boom", all making lots of noises that some sound technicians likely spent hours in a studio putting together. And, most of the time it seems, these films get space completely wrong. 

Humans cannot hear in the vacuum of space. We can't. Since sound waves need a medium through which to travel and space generally offers nothing of the sort, there will be no propagation of sound from space battles, Star Destroyers traveling past you, or your fellow astronaut screaming from inside their space suit as they drift away from the ship after forgetting to attach their tether (unless, of course, they're screaming into their radio communication system).

Check out this vid from Coma Niddy at Sci Code on Space Myths

Star Trek, Star Wars, Battlestar Galactica, and more: the sounds of the spaceships and space battles and other spacey stuff in most of our television and films seem to show an utter lack of understanding on the part of the populace general. Even if filmmakers know that there shouldn't be sounds in space, it seems like most of them pander to the ignorance of the people by adding sounds to space. There are some who get it right, though. The cult sensation Firefly was well-known for presenting the lack of sound waves in space. 2001: A Space Odyssey, Gravity, and a few others also present the silence of space to the audience.

But hold on now, you might be thinking. Slow your roll, Cosmo Boy. Perhaps you've heard that NASA has recordings of some sounds from space. So what's up with that?

Just because sound waves don't generally propagate through space doesn't mean there's nothing for us to hear out there. For instance, several spacecraft (including the Voyager, Injun, and Hawkeye spacecraft) have had instruments capable of detecting the interactions of various particles with the ionospheres and magnetospheres of planets as well as the solar wind. The electromagnetic interactions spread over a large range of vibrations, but a lot of them are in the 20-20,000 Hz range in which we humans hear. NASA has released lots of these sound data sets online, including files primed for ringtones and notification sounds. Here's a video compilation of some of these sounds from our solar system (definitely awesome!):



Pretty cool, huh?!

Well, guess what? There's more.

As if listening to the interactions of the planets with the space environment weren't awesome enough, we can also take data from many our observations of the universe and convert those data into sound files. This is done through a process called sonification. For instance, we can take the Kepler light curves of stars and convert those light curves into sounds, allowing us to listen to the data. We can listen to the variations in the stars and we can even listen to the dips in the light curves as exoplanets transit in front of the stars. 

Sounds that are produced in this way aren't anything you would naturally hear, but they're still pretty awesome. For instance, this video presents a chorus of sounds produced through the sonification of light curves:



That's some eerie stuff. We can use sonification to convert all kinds of data into sounds, but listening to the processes occurring so far away in some way seems haunting and yet inspiring. Pod Academy recorded an episode called The Sounds of Space back in 2012 which can give you a fuller description of some of the cool stuff that what we can listen to from our observations of space. It's definitely worth a listen.

So even though no one can hear you scream in space, and even though all those spaceships going "pew pew pew" with their lasers and phasers and such in science fiction movies is a bunch of silliness (even if it does sound cool), there are some awesome things that we can really hear from our observations of space, either actual interactions of matter that cause vibrations in our hearing range or from data that we've converted to sounds. 

If you'd like to hear some more, I have another post to accompany this one that includes several embedded videos with the sounds from some of the worlds of our solar system.

(Image from PRX)