One-Planet Graves

“The universe is probably littered with the one-planet graves of cultures which made the sensible economic decision that there’s no good reason to go into space—each discovered, studied, and remembered by the ones who made the irrational decision.”
Randall Munroe(xkcd)

 

We’ll see the start of a two planet culture in the next 20 years. However it will probably take 500 years to really make a solid civilization there. In 500 years will there be somebody at a keyboard wondering about “One-Solar Graves”? Perhaps I should be the first to modify the above quote to:

“The universe is probably littered with the one-solar-system graves of cultures which made the sensible economic decision that there’s no good reason to leave their star’s solar system—each discovered, studied, and remembered by the ones who made the irrational decision.”
Ivor O’Connor

When looking at historical moments in a species race what would they be? Flight? Computers? Internet? Satellites? Stable environment run with renewable energy? Colonization of other planets in their solar system? Colonization of interstellar space? Colonization of multiple star systems? Colonization of multiple galaxies? Something beyond this… Ten steps. We are at step 4 attempting to make it to step 5 in my view. Perhaps looking at step 6 will help us achieve step 5 faster…