Transcript:

Hi! We literally are stardust. Let's look at how the elements in our body get formed. It all begins with hydrogen. The lightest element is hydrogen. When massive chunks of hydrogen comes together, gravity pulls them closer and closer and closer, and eventually, hydrogen will fuse to make helium. This is what's happening in the sun. Hydrogen fuses to make helium and releases a lot of energy.

And this fusion process continues. So hydrogen fuses to helium, helium fuses to carbon, carbon fuses to oxygen, oxygen fuses to silicon, and silicon fuses to iron. And iron is a very stable element. Once iron is formed, gravity just takes over because there's nothing to push against gravity. There's no more fusion below helium, below iron. So gravity takes over, and all the outer gases get compressed, and there's a rebound force because of what is called degeneracy. But that's a technical term. It just means that nothing can occupy the same space more closely than a limit.

So there's a repulsion force, and that repulsion undoes hundreds of thousands of years of fusion, and then the iron is disintegrated into smaller elements and thrown out into the universe. And then those elements coalesce to form planets, and that's how we are stardust.

Now you know.