We often think of space as a vacuum, an empty region of well… space… But it’s not. Those who study very cold, very clean vacuums see space as hot, very dirty, and filled with many things. Yes, if you are floating out in space, you can not hear sounds - you need more matter to transfer the sound waves we hear on Earth - but radio waves run wild across this vast expanse. So, let’s take a look at some of these sounds from space (i.e. not Earth).
Some of the initial sounds we heard from space were accidental. As to who heard them first, I’m not sure we will ever know. However, there are two likely groups. Telegraph operators noticed odd noises that seemed to come about with the auroras, and British soldiers during WWI heard similar sounds (sounds of a falling tone) in their communication amplifiers. These sounds came from space. The waves are moving along magnetic field lines - with the higher frequency waves arriving first and then lower frequency waves later, giving the characteristic sound of someone whistling… or a bomb falling. Thus, these waves were called “Whistlers”. These radio waves, besides just sounding cool, tell us a lot about the space around the Earth. They tell us about the plasma and how it moves and changes. And they can also tell us how space weather impacts our society and technology.
As it can be computationally expensive to process a lot of data - especially in the early days of computers, many convert the data to sound to find events. This led to some fantastic names. We are not the most creative bunch regarding names, as you may understand by now if you have read my posts. The waves that seem to occur in the morning and sound like birds chirping? We’ll call those The Dawn Chorus. Those that sound like a cat or people hissing? We’ll call them Hiss waves.
But these waves are not confined to occurring only in space around Earth. Whistler waves are heard around other planets, like Jupiter.
They sound very similar—but they are different because the magnetosphere and plasma within Jupiter’s magnetosphere are different from our own. However, studying both gives us a better understanding of our Earth's magnetospheric system and how these phenomena change and impact our technology.
Radio waves are also not confined to planets or our solar system. They can be found throughout the universe. They tell us about other galaxies, stars, and even other exoplanets. However, radio waves are not the only way we use sound to understand the universe better.
We can take data that already holds a lot of information and visualize it. Each colour means something; the location of the colour and data tell us something, but there is so much more to know. We can either take that same data and translate it to music or add another layer of data to it using sound. Either way, it provides a new, unique way to experience the data and a new way we might understand what it is trying to tell us.
This sonification can also help us communicate science to others who may not be used to thinking about data analysis methodologies, who might be turned off by science, and who might be intimidated by science. (Science should never be intimidating, but then writing should also not be intimidating, and it totally is for me.) So we can turn to musicians to help us sonify, if that is a word, the data to ensure it is pleasurable to listen to and helps us reach audiences that we might not normally talk about science to.
And with these methods of looking at, listening to, and ingesting the data into our minds, we deepen our understanding of what is happening and how the world is changing.
We can also use sound to learn more about space and our solar system—not radio waves or sonification; but sound in the human audible range. The Perseverance Rover was the first rover with a microphone in space. This has allowed us to hear what things sound like on another planet.
We can hear Ingenuity, the little helicopter, fly on Mars.
We can hear the rover itself move across the Martian landscape.
We can hear the wind on Mars.
It all sounds a bit like Earth, like our home. This is another way we can see the similarities and differences between our two planets and learn about what makes Earth so unique. It is another way to experience space. The universe is beautiful - both visually and audibly. And it’s high time we listen more closely to this masterpiece.*
*Yes Prof. PlasmaNerd hates it when I equate science and math to a symphany… but it is! The universe is a beautiful symphony.
And if you made it this far, enjoy a Solar Wind Sea Shanty.