eli5-how do we know for sure how big space is? and how do we know we are right about everything we know in space?

Question

eli5-how do we know for sure how big space is? and how do we know we are right about everything we know in space?

In: Planetary Science

Answer 1

We don’t know how big it is. And many of the things we thought we understood about space have been proven incorrect over the past decade or so. Your guess is as good as mine. Or something like that.