> so long away Even if it'll take 500 years to achieve, which seems longer than realistic, that's still the blink of an eye on a cosmic timescale. A comet or

> so long away Even if it'll take 500 years to achieve, which seems longer than realistic, that's still the blink of an eye on a cosmic timescale. A comet or asteroid could hit us at any moment and cause our extinction. That's one example of a planet-specific existential risk. Diversifying life across multiple planets would make it much more likely that we'd survive as a species if something like this happened.