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.

To hear it and every episode early and add free, plus hours of bonus content,

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

We imagine cities among the stars. What we will build are constellations of worlds.

Humanity may one day build a billion new worlds, not by terraforming alien planets, but by assembling

them, piece by piece in the void.

But just like we rarely build a single house without a road, a neighbor, or a community,

our space habitats may not be solitary wanderers, there may be parts of greater holes,

living clusters, orbital tapestries, civilizations among the stars, not scattered but woven

together.

Today, to celebrate the 11th anniversary of our very first episode, megastructures and science

and science fiction, we will explore the future of space habitat clusters and conglomerations.

From simple daisy chains of or neoc cylinders to vast, modular megastructures, bristling with

life and purpose, we will look at why these habitats come together, how they share energy,

culture, and security, and what strange new shapes are homes among the stars might take.

Because when you have the power to build worlds, the next question becomes, how do you connect

them?

Why clustered habitats?

When most people imagine a space habitat, they picture a lone cylinder or a tourist drifting

serenely through the void, like a futuristic Noah's Ark set

against a backdrop of stars. But just a single house doesn't make a city, or even a village.

...