Hello, SFIA audio listeners.

In this month's Nebula exclusive, big alien theory,

we're asked at the reason alien civilizations might be rare

is because most aliens are huge.

To hear it and every episode early and ad-free,

plus hours of bonus content,

check out go.nebola.tv slash Isaac Arthur and use my code, Isaac Arthur.

Civilizations grow on energy, and the greatest power source in reach is the star we orbit.

So what happens when we stop being children of Earth and become architects of the sun?

And what kind of commerce emerges when an entire solar system starts doing business with each other?

What is the Dyson swarm? And why build one?

At a basic level, all of our power comes from the sun, and we use only a tiny portion

of the mass amount that survives on Earth, and yet that massive energy supplies but a tiny fraction of what the

Sun provides, not even a billionth. Once we came to realize that we had scientists and futurists

like Dyson, Cardishev, and Stapernan, begin wondering if the inevitable fate of humanity,

or any alien civilization, is to englobe their star in a sphere to use most of that energy.

A Dyson swarm is not a solid shell encasing the sun, like you might see in sci-fi for a Dyson

sphere. It's a vast, growing forest of satellites, habitats, and energy collectors orbiting a star,

each like a solar-powered leaf capturing sunlight.

Individually, they are modest.

Collectively, they could harness nearly all the energy our sun produces, over a hundred

trillion times more than we use today.

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