You know what time it is. This time for Ask a Space Man. I'm your host, Paul Sutter. You've got questions and I've got answers. You know how this show works, but let's run through it step by step. You go online

to Twitter or Facebook. Use the hashtag Ask a Space man and I might just pick some questions to

answer on this show. I know how awesome is that. If you don't like Twitter or Facebook, I don't

blame you. That's cool. There's room enough for

everyone at the table. You can email Ask a Spaceman at gmail.com. You can also go to Askaspaceman.com.

And then you'll find all the episodes, show notes, all that stuff. There's a little comment

section. You can add questions there. It's all good.

However you want, send those questions to me. You can also follow me directly on Twitter and Facebook.

My name is Paul Matt Sutter. We have a very simple goal with this show. It's trivial, really,

complete knowledge of time and space, and we'll get there get there don't worry one step at a time

and on that road to complete knowledge of time and spaces today's question from harold just just

just harold that's all i got harold are sephe's really constant and how does the distance ladder work?

That is such a great question. I love questions like this. I love questions about how we know stuff

because there's so much in astronomy, especially astronomy that's presented to the public

like I'm doing right now that has just taken for granted like we'll

just say something like such and such galaxy is it such and such and such millions or billions of

light years away and you just take it for granted like yeah it's really far away knew it but think about it

like even a hundred 150 years ago, our conception of the size of the universe was so much smaller than it is today.

We thought the Milky Way was it.

That was it.

The whole entire universe was the Milky Way.

There's just a whole bunch of stars.

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