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.

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This episode is sponsored by Brilliant.

The trick to designing any machine, especially a spacecraft, is knowing what its purpose

and mission are.

Unfortunately, science fiction provides us with few ships designed with those concepts in mind.

Music designed with those concepts in mind.

So today we'll be looking at spaceship design from modern ships to those of the distant future to some that might never exist outside of science

fiction.

We'll also be deconstructing some sci-fi designs to see if they really make that much

sense, and examining some real-world design elements that are specific only to modern

spacecraft.

Right now, every spacecraft is designed to be as light as possible because every kilogram

costs a lot of money to get into space.

Also, spacecraft are most commonly lost in the launch phase, so if you want to assemble

a bigger ship or station orbit, you need a lot of launches, each of which might blow up

on the pad or shortly after launch.

And even for automated launches, that results in missions exceeding budgets and introducing

big delays. And so, in modern space exploration, if you can make a hammer that weighs

half as much but costs a hundred times as much, you send that expensive hammer-up instead of

...