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 the show we look at vast interstellar empires or massive megastructures, civilization

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 is livable, represents less than the quadrurieth 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 a desert of tundra.

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