Explained: How scientists capture sound from space
Space is a captivating and mysterious environment, full of incredible structures and phenomena. But have you ever wondered if sound can travel through the vacuum of space? Well, no. But it would definitely be inaccurate to say that space is silent. Scientists have developed various methods to capture and analyse the sounds in space. By studying these sounds, they can gain a better understanding of the universe and its many wonders. Recently, NASA captured the sound of a black hole! Do you want to know how? Keep on reading.
Space has sound too
You can hear sound on some celestial bodies like earth, and moons. This is because these celestial bodies have a medium, such as an atmosphere that allows sound waves to travel. But what about space? Some argue that space is silent because it is a vacuum (an area without medium) through which sound cannot travel. However, this is not entirely correct. There are particles and sound waves in space as well and sound waves are nothing but vibrations of small particles in pressure. In space, the pressure changes are very small. As a result, we cannot hear the sound waves. Moreover, the frequencies are too low for us to hear. You would need an eardrum the size of the earth to hear them!
But NASA has special tools that can listen to these sound waves in space. And two of NASA’s technologies have proven particularly useful in this matter: The Van Allen Probe and the sonification technology.
The Van Allen Probe
The scientists at NASA developed a technology called Van Allen Probe in 2012 to catch the sounds of space. The probe has a wave instrument called Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS). The EMFISIS is like a giant microphone that can catch sound waves that are too low for humans to hear. It picks up vibrations caused by small particles floating closer to the earth and then converts them into sound. It's similar to how you can listen to music coming out of a speaker: the music is a pattern of vibrations your ears can detect and interpret as sound.
The sonification technology
If you are a space enthusiast, you are probably aware of the news that NASA has captured the sound of a black hole. Aren't you curious about how they did it? As previously mentioned, sound needs a medium to travel and galaxies already have a large amount of gas. So, you know what that means: A perfect medium for sound waves to travel! And that is exactly how NASA captured the roar of a black hole in a galaxy cluster called Perseus. The sound emitted from the black hole was 57 octaves below the middle C (musical note), basically, way too low for us to hear. So, NASA amplified the sound through a process called sonification. Through this process, the sound waves were extracted and scaled up by 288 quadrillion (or 288 million billion) times higher than the original sound. Amazing, isn’t it?