[Physicist]

How can they ever know how old the universe is?

By looking at the evidence. The universe obeys physical laws, you know.

These people actually get paid to make educated guesses like this?

No, they get paid to make measurements like this.

Where can I get a job like that?

You start by spending twelve years in college (as I did).

[Reaganwuzthebest]

What does college have to do with anything? I've got six behind me, so what? With all of our technology, we still haven't scratched the surface of what's out there. You can measure till the sun goes down, it's still all theories. You've got some scientists saying the universe is expanding, while others say no no, it's contracting. They haven't got a clue, neither do I, and neither do you.

[jlogajan]

You start by spending twelve years in college

Oh heck, I could do that. :-)