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.t.v. And use my code, Isaac Arthur.

In the future, humanity may travel to many strange new worlds and make homes on them,

but we may also build is space habitats, but usually

we're either discussing one specific type out of mini, like the or a new cylinder, or

we're just mentioning them

in passing as this sort of inevitable future for all mankind.

Folks coming to the channel can be surprised sometimes how we talk about them less as things

we might build a few of, and more as a mass-manufactured archipelago that will eventually

house the super majority of humans instead of planets being

their main homes.

Space habitats are very different from a basic space station like those we have now and

are cost prohibitive until we have a much larger presence in space, like mines and forges

on the moon, as well as greater energy abundance and better automation

that is able to handle much of the production, so humans aren't individually welding

each plate of the habitats floor together by hand. It is very likely though that we will reach

those benchmarks inside this century, in which case much as high rises and skyscrapers become economical

with cheap steel, enormous cylinder and ring-shaped habitats, spinning to produce artificial

gravity, may become much cheaper than trying to buy any free space on Earth, where land

values are likely to keep rising as we simultaneously grow in numbers and try to grow the number of protected

...