Hello, SFIA audio listeners, in this month's Nebula exclusive, Big Alien Theory,

we're asking the reason alien civilizations might be rare is because most aliens are huge.

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Sometimes the future is not so bright, so you have to make your own light.

So often on this show, we look at vast interstellar empires or massive megastructures, civilizations

so enormous they could fill entire planets just with everyone born in a given minutes

of a given day.

So I thought today we would look at a smaller civilization, those who occupied not planets

around distant stars, but the vast gulfs of space between those stars.

It's strange to think that our planet occupies

only a very tiny portion of our solar system, getting less than a billionth of our sun's

light, and yet that vast pocket of space, worn by our sun, to the point it as livable,

represents less than the quadrillionth of the volume of space, nominally influenced by our sun,

rather than one of the neighboring stars. As we go out to colonize the outer solar system, where the sun is still quite bright compared

to any other star in the sky, and into the galaxy to make homes around those stars, and we consider

colonizing those other distant galaxies, it is so easy to forget that each of those is but a tiny

island in a vast nothingness of

empty space, and yet it is not actually empty, even it is far more barren than the desert

...