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 add free, plus hours of bonus content,

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

They say if you join the Navy, you'll see the world.

But if you join a space fleet, you might see several.

Of course, what you'll mostly see is an awful lot of nothing.

Space is big, really big. Just beyond immense and enormously huge. It contains everything there is, and yet what it mostly contains is an awful lot of nothing whatsoever.

This can make it a bit difficult to visualize properly and also means that spaceships

fighting each other in the void can be tricky to show in an exciting and realistic way.

Indeed, while modern CGI lets even lower budget TV shows display thousands of ships fighting at once,

not just one or two plastic models, we still have the challenge that even the best

CGI can't really help with.

And that's how empty and unexciting actual space is compared to the World War era battleship

engagements or airplane dogfights, we tend to use

a basis for naval conflicts in space.

And that's a good place to begin our discussion of space combat and battle fleets, our habit

of viewing everything as naval analogies.

Space is not an ocean.

I love those science fiction tales that portray it that way. I love

the poetry of thinking of it as the ocean of the night, and I use it myself a lot, but it's just

not true. Even the more three-dimensional perspectives of contemplating spaceships as submarines

...