[avz]

I think the situation with interstellar travel is well summed up in this conversation between TARS and Cooper as they attempt to dock at Endurance (intentional pun hiding in movie title):

TARS: It's not possible.

Cooper: No, it's necessary.

It seems impossible, but if we don't pull it off we die. And I don't mean we the few folks on HN. I mean everyone.

Earth is a graveyard of species. Nearly all (99% IIRC) species that ever existed have gone extinct (most before we showed up). As a species, we can't stay here and live. A 9-mile thin layer of gas over a single small planet is just not a reliable long-term basis of survival. In fact, the fragility of our tiny little habitant is on display right in front of us this century.

[Juliate]

That’s a very anthropocentric, exceptionalist take.

Earth is as much a graveyard as it is a womb and a home and a paradise.

It’s frail compared to what’s outside of it. But it has quite a record (the only one known so far) of making life possible, for millions of years.

There’s nothing we know of this scale and capacity and resilience and welcoming to us (not only humans).

[AlexanderTheGr8]

tbh I never really understood that conversation. TARS is a machine and if it's impossible from an advanced machine's standpoint, it's impossible from a physics standpoint. Cooper's maneuver was pretty simple that TARS should have been able to simulate and figure out.

Regardless, I agree that being multi-planetary is absolutely a requirement for humanity. We are too risky here. And the risk is not from outside. Humanity has survived for 100s of millions of years without as asteroid annihilating us, and I don't see it changing now).

The biggest risk to humanity is humanity. We will probably figure out a way to destroy ourselves, either with something much more powerful than nuclear bombs or some new unimaginable tech.

[avz]

Single planetary system isn't much more of a protection than a single planet against some of the possible extinction events, e.g. ones associated with the activity of the Sun or intelligent aliens.

> Humanity has survived for 100s of millions of years without as asteroid annihilating us, and I don't see it changing now).

Homo sapiens is thought to have existed for mere 300,000 years. Our last common ancestor with the chimpanzee [1] existed no more than 13 million years ago. K-T extinction event [2] that wiped out dinosaurs happened 66 million years ago. There have been numerous extinction events before and after that [3].

On the timescales of species this planet isn't safe. At these timescales rare events become regular occurrences.

[1]: https://en.wikipedia.org/wiki/Chimpanzee%E2%80%93human_last_...

[2]: https://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene_e...

[3]: https://en.wikipedia.org/wiki/List_of_extinction_events