[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.