What Causes the ‘Sound’ of Thunder and Why Does It Happen After a Flash of Light?

Thunder is the sound we hear when lightning happens, and it comes after the flash because sound travels slower than light.

Lightning is super fast, like a blink of an eye! The light from lightning zips through the air so quickly that we see it almost right away. But the sound, or thunder, takes longer to reach us because sound moves more slowly. It's like when you see a rocket take off and then hear its engines a little later, the light gets here first, and the sound follows.

When lightning strikes, it heats up the air around it really quickly. This hot air expands and pushes against the cooler air around it, making a big boom, that's thunder! The farther away you are from the lightning, the longer it takes for the sound to reach you. So, if you're far off, you might hear a loud rumble after the flash.

That’s why thunder sounds magical, it’s like the sky is talking to us, with light and sound playing tag!