The more you know

It's been estimated that it is so

Nah but if you know how long ago it began, and the rate at which it's expanding, you can figure out the rest. It's not 100%, but I think they have good reason to be confident in their numbers

The problem is that we don't know if it always was like today. Some scientists even think that the expanding of the universe was faster / slower and the speed is changing. So all the calculation based on the speed are wrong if this is true. + we don't even know if the "big bang" is real or if there is maybe something complete different behind the phenomena we see today. Scientists even seem to jave found proofs for a universe before our universe.. Like.. Our universe got created from another one. Etc etc.. Maybe there is even far out there more we cant see / know.. Outside of our universe as an example.

Imagine this: our universe does exist in a "bubble", and this bubble is floating within a "void". And in this void there are a lot of other bubbles which all have too a universe in them. And the amount of this bubbles is like the stars.. A huge mass of bubbles. And the "expanding" just lets the bubbles get bigger. If this is true, there are more stars than you can even imagine.