Always there. Here's an ELI5 from Bing:

The article is about a very quiet sound that comes from space. The sound is made by things that are very big and heavy, like giant balls of fire or holes that suck everything in. The sound is so quiet that we can't hear it, but we can use special machines to find it.

The article says that this sound is all around us, and it comes from different places in space. Some places are very far away, like other stars or other worlds. Some places are closer, like our big family of stars. The article also says that this sound can help us learn more about space and how it works.

The article is very cool because it shows that there are many things in space that we don't see, but we can find them by listening to the sounds they make.