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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Science fiction delights in showing us humanity's future on strange new worlds we will find out among the stars.

But it is very likely our future will be on massive

artificial worlds and megastructures of our own creation.

So welcome to Science and Futurism with Isaac Arthur, and I am the aforementioned host,

Isaac Arthur. Just under eight years ago, the channel began with an episode cataloguing a number

of what we call

megastructures, huge artificial constructs that in many cases would rival entire planets in size

and serve a similar role as our future homes. Back in the day, the graphics on the show weren't

terribly impressive. Indeed, most megastructural visuals in existence were made after that episode,

mini for this show, and the audio was terrible. It was the first episode of the show,

and the only one not to include the episode transcript in as captions because there wasn't one.

As time went on, our audio and graphics improved, and I got some speech therapy for my

speech impediment, and folks often asked why I've never redone that episode when almost every other

early episode has gotten a redo, or reboot, or even an entire extended series. Indeed, we gave

many megastructures their own episode in our Megastructure series, but it didn't

indeed seem time to catalog all of them again in a summary form, including many new ones

...