We know that there is sound on planets and moons in the solar system – places where there’s a medium through which sound waves can be transmitted, such as an atmosphere or an ocean. But what about empty space? You may have been told definitively that space is silent, maybe by your teacher or through the marketing of the movie Alien – “In space no one can hear you scream”. The common explanation for this is that space is a vacuum and so there’s no medium for sound to travel through.
But that isn’t exactly right. Space is never completely empty – there are a few particles and sound waves floating around. In fact, sound waves in the space around the Earth are very important to our continued technological existence. They also they sound pretty weird!