ELI5: Explain Like I'm 5

Stellar nucleosynthesis

Hey kiddo, do you know what stars are made of? No, not just light and heat, but actual stuff! Well, long ago, in the beginning of the universe, there was only hydrogen, helium, and a teeny tiny bit of lithium. But then, over time, stars were born and they helped make all the other elements we know today. This process of creating new elements is called stellar nucleosynthesis.

So, what happens is that stars take in hydrogen gas and their gravity pulls it into a super hot, super dense core. This creates a lot of pressure and heat, causing the hydrogen atoms to fuse together to make helium. That's right, they stick together to become a new, bigger atom!

But stars don't stop there. They get even hotter and denser as they fuse more and more atoms together, creating heavier elements like carbon, oxygen, and even iron! This fusion process creates a lot of energy which is what makes stars shine so bright. And when the star has used up all its fuel, it explodes in what's called a supernova, scattering all the elements it made out into the universe.

So, there you have it, Stellar nucleosynthesis is the process of stars creating heavier elements from the fusion of lighter elements. It's how the universe was able to make all the different kinds of elements that we know and love today!