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.

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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, 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'll 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 herald

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 you know

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 100, 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, and that's it. And the Andromeda galaxy back then was just the Andromeda Nebula. It was just a fuzzy patch of stuff up in the sky that was a part of the Milky Way. And it wasn't until we started developing more accurate methods for determining distances to other

stuff up in space that our minds were blown, that we figured out just how big this thing we call

the universe really is. And it all comes down to measuring stuff that's far away. And there's a few methods

available. And I'm going to run through them because that's like the point of this episode.

So let's start with something simple. Let's start with something simple. If you're,

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