Once upon a time, 13.8 billion years ago, all energy and matter in the universe was crammed into singularity, smaller than a grain of salt.

That's a super long time ago!

Suddenly, everything started to expand, and eventually the universe cooled down enough for galaxies and planets to start forming and it hasn't stopped expanding since.

So how do we know that the big bang even happened?

A big piece of evidence astronomers have found is something called the Red Shift. The Red Shift is a theory that light from galaxies that were created during the Big Bang is just now becoming visible to astronomers

Another big piece of evidence astronomers have found is something called Cosmic Background Radiation. 

What is that?

Cosmic Background Radiation is just radio waves that can be heard at any possible point in the universe

Do you think the universe ever stop expanding?

Well I think since it has been expanding for 13.8 billion years, I have no reason to believe it will ever stop expanding.

And that's the story of how it all began,

                                            The End