ELI5: Explain Like I'm 5

Cosmic ray

Hey kiddo, have you ever heard about cosmic rays? No? Well, let me tell you all about them!

You know that our planet is surrounded by something called the atmosphere, which is like a big blanket of gas that keeps us alive by trapping air and protecting us from the sun's harmful rays. But high up in space, there is no air or atmosphere to protect things like planets and stars, so they are bombarded by tiny particles called cosmic rays.

Now, these cosmic rays are like invisible bullets that are constantly flying through space, travelling at amazingly high speeds. They are made up of tiny subatomic particles that come crashing down onto Earth's atmosphere where they cause a lot of excitement among other atoms and molecules.

So imagine playing a game of pool, where you hit the white ball into a bunch of other balls which then scatter all over the table. That's what happens when cosmic rays hit the atoms in our atmosphere - they cause a bunch of collisions and energize these atoms, creating new particles that can cause very noticeable effects down here on Earth.

Sometimes, these cosmic rays can even cause bright, colorful displays in the sky, like the Northern Lights or Aurora Borealis. So next time you see one of those beautiful, shimmering lights, you'll know that its happening because of tiny, high-speed particles zooming around in space!