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.

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

This episode is sponsored by Audubal.

Space is huge, spanning an enormity of space and time that staggers the mind.

Such being the case, it is not hard to imagine entire planets being forgotten, colonies lost.

Some even believe Earth itself may be one such lost colony.

Welcome back to SFIA for another sci-fi Sunday, where we relax our focus on science

a bit to ponder science fiction concepts and ask how realistic they are.

Today we are contemplating the idea of lost colonies, as part of our rogue civilization series

where we have looked at prison planets, trash worlds, nomadic interstellar civilizations,

techno-barbarians, space pirates, and many more.

Now on the one hand, the notion a colony might actually get lost seems unlikely.

The galaxy may be huge, but even a catalog and wiki of a trillion stars easily fits on a modern

hard drive, and adding the planets of each system shouldn't

be any challenge for an interstellar empire either, even with millions of backups.

So too, people won't ignore a whole star system within a few dozen light years of their own,

and we expect most star systems to get colonized.

On the other hand, that is contemplating a hypothetical galaxy a million

years from now or more when the whole place is settled. It is also assuming anything like

an organized data transfer and verification system occurs. In terms of bribes, how expensive

...