>>10990815Go colonize Mars and in the process you will build out and gain loads of experience with an interplanetary transport system fleet, which will give you a chance to respond to a discovered object on a crash course with Earth in time to maybe divert it.
Go further and colonize Mars, Moon, and the asteroid belt, and now the only thing you need to really worry about are comets and gamma ray bursts from other stars.
Go further and colonize out to the Kuiper belt and now you aren't just catching and diverting every dangerous object a little bit, you're strip mining them down to nothing and building them into nice comfy space habitats, but you're still worried about gamma ray bursts.
So you go further and start spreading across multiple star systems, not need to move quickly just coast between stars at 1000 km/s in giant flotillas of generation and factory ships, stop briefly in each star system you pass by to build out a decent seed colony and replenish your fuel and resource supplies before leaving again, continuing to spread in all directions and slowly converting every star system you colonize into a Dyson swarm of quadrillions of habitats containing millions of people each until you've colonized a few hundred billion stars and the human population is up in the nonillions, and you're pretty sure you're not gonna get set back by a GRB any more (especially since you went ahead and put preventative measures in place around every likely GRB candidate star that will prevent that from happening in the first place.
But the Andromeda galaxy is heading towards the Milky Way, and it could also flare up its central black hole and the matter jet could cause problems, so better get over there and colonize that too, so a few hundred trillion of your black-hole engine propelled megaships start leaving the galaxy boosted by stellaser highway up to close to light speed and coast across for a few million years . . .
