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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check out go.nebula.tv slash Isaac Arthur,

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Black holes are objects of mystery and dread from which nothing can escape, but they could

also be the foundations of future civilizations of unimaginable might and size.

Black holes are interesting objects that have fascinated us both in science and science fiction,

but their portrayal in science fiction, and even often science, has tended to be flawed and included a lot of misconceptions.

We'll be clearing those up today as we discussed technological applications we

might have with black holes and seeing how they might be the centers of future civilizations,

metaphorically and even physically, not their destroyers.

Though we'll also be examining weapons based around black holes, including the Krasar

cannon, Ophoff gun, and Black Hole Bomb.

We need to start with the key misconception though, and that's the idea that black holes

are these invisible monsters that sneak up on you and for which you cannot escape.

In reality it's very difficult to get sucked into one, especially before you notice it's there.

Your typical black hole is the leftover remnant of a star so big that it stretched millions

of miles across and would be lethal to anyone within hundreds of millions of miles of it.

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