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 ad-free, plus hours of bonus content,

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

As humanity grows ever more reliant on machines, we may begin using them more and more in

our own bodies, with many becoming cyborgs, possessing vast augmentation to body or mind.

A civilization built upon such a difference may be a strange one indeed, and may be just

over the horizon.

Over a billion miles from Earth lies the dwarf planet Orcus, a frigid rock over 500 miles across

that no sane man would want to live on, where

the temperature is even lower than on Pluto.

And yet, it was too vital a strategic resource to go unsettled even during the early

days of solar expansion.

The settlement there was never very well funded, and in many ways existed merely to cement ownership

by having a present and active colony base. Indeed, they often had to attract colonists from any

place willing to send them, or often as not, people who came there with a past they wanted

forgotten, and no previous home they wished to claim.

The original nation that successfully claimed it fell to history's wayside, leaving it in

a rare position of finding itself independent without having to fight any battles, with

fleets or attorneys.

The citizens there were not entirely thrilled at their new status, for they found themselves

in the unenviable position of being cut off from any support. Forced to live on a frozen rock

...