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.

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plus hours of bonus content,

check out go.nebola.tv slash Isaac Arthur,

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They say space is the future out among the countless billions and billions of new worlds in

all galaxy, but a journey needs a path or road, so what sort of roads will we build in space?

No. in space. Underneath almost every house or building, humble or grand, is a foundation and often a driveway to a road, power lines, water lines, sewer, telephone, cable, internet, and more.

There are roads and rails, highways, airports and train stations, pipelines and high voltage

cables, cell phone and Wi-Fi networks.

Sea ports, water treatment facilities, power plants, hospitals, schools, police and fire station,

banks and ATMs, mince and now even crypto mines, police and fire station, banks and ATMs, mints, and

now even crypto mines, parks and walkways, software updates, hiking and biking trails, and

so many more.

These are but a sample of the infrastructure that our civilization on this planet runs on,

and I thought we would ask what that looks like at the interplanetary

scale, as our civilization spreads out to other major planets, moons, and millions of

minor planets and asteroids orbiting our shared sun.

At the core, infrastructure is the facilities or systems that serve some place, be it a tiny

...