[dougmwne]

Space is much bigger than you are accounting for and the speed of light much slower. If the nearest spacefaring civilization is in the next galaxy over, we will never meet them. It actually seems rather unlikely any spacecraft could ever reach us unless they evolved right in our backyard, within a few dozen light years.

[polishdude20]

That's also IF the life is space faring. We haven't even found life anywhere that is at least remotely simple let alone one that has built spacecraft.

[dougmwne]

But to be fair, it’s not like we’ve been able to look very many places. We’ve checked a few of the planets in our own solar system and it could be plausible to detect a civilization within a few light years by radio wave if we were very lucky.

https://physics.stackexchange.com/questions/245505/from-how-...

[wruza]

It’s also extremely hostile to anything non-trivial like biology or electronics. We all have that cool space-faring ideas in mind from scifi, but reality is more like swimming in a tiny boat through the storms of Pacific Ocean and it’s acid.

[chongli]

That perspective is a somewhat human-centric one. There’s nothing stopping some aliens from having lifespans in the thousands or even millions of years. For those cultures, a 300 year trip is nothing!

Furthermore, Andromeda galaxy is on a collision course with the Milky Way. If there’s an intelligent alien culture there, they might get here just by waiting.

[dougmwne]

Well we reproduce so it’s really the same difference. The huge limiting factor for getting between stars seems to be the rocket equation. You have to invent magic propulsion to cross the galaxy.