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 ad-free, plus hours of bonus content,

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

The Road to Eternity is even longer than the roads between stars, and some may choose to sleep

and dream away the eons. Perhaps we might encounter such dreaming empires out among the stars,

though such an encounter may awaken nightmares upon the galaxy.

The space between galaxies is even emptier than the space between stars, but sometimes

you come across stars out there, and for those multi-million-year journeys between galaxies,

as we reached out from the Milky Way to the neighbors beyond, we paused on those

journeys and even zigzagged to settle those systems we did find. This would help form a bridge

of stars between galaxies and allow more missions to follow one day and contact to remain along

the bridge. When a splinter fleet breaks off from the main intergalantic armada to settle one of these

bridge stars, its main goal is to erect the massive energy beaming systems around that star

that will relay communications to neighboring bridge stars and helps slow or speed up any ships

that come by, journeying between

stars. At Midway Station, over a million light years from Earth, the settlers knew no customers

were coming behind for at least a million years, as they were an unplanned system,

originally bypassed or having a red giant binary system in it.

That binary giant exploded as a supernova long after they locked in on a different

original path for the armada, but it was a more direct route, so their splinter was to settle

and build up this more straight-line node in their bridge, far, far-headed time.

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