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.

We often dream of future out in the galaxy, exploring and settling strange new worlds

under the light of alien suns.

But what would living in space truly be like?

Last week we were talking about Neo-Term space colonization and some of the holders we would encounter on our journey to settle new worlds, but we didn't talk much

about what living in space itself would actually be like and what the challenges

for humans are when living off

Earth.

It's a big topic because space is big, really big, you just won't believe how vastly,

hugely, mind-boggling the big it is, and that also means that there are a lot of different

conditions humans would need to adapt to in order to live in those places, or adapt them to all needs, or possibly meet somewhere in

the middle, as we often have in our history on just this single world and its many different

climates and ecosystems, which again is but one world among billions and billions.

Now we're not talking today about living

in the actual void of space, which is empty of everything life needs and plentiful in

harsh radiation and high-speed micrometears. We contemplated biology adjusted to the vacuum

in our episode Void Ecology, but today we're principally interested in how life can be

adapted to space settlements we build, or those settlements we build on planets, moons, comets,

or asteroids.

...