[jrd259]

Suppose we did get 100 year advance notice of some catastrophe. How many people would call it "fake news", or perhaps even interpret it as part of "God's plan"? Let's suppose, through some miracle, a substantial majority of the world agrees the catastrophe is coming, agrees to cooperate, to accept unlimited damage to the Earth (so e.g. we can use Project Orion style launchers) and to give up on all short-term profit.

Our response to climate change (which, even if it's not at the level of total planetary extinction, is still quite serious) suggests we would instead obfuscate, dispute and quarrel.

Realistically, what fraction of the world's people could we possibly move to Mars, and how would we even pick those people? How would we even come to agree on a fair way to choose?

We probably could get enough breeding pairs there to preserve our species. There is evidence of genetic bottlenecks in the past. But 99% of humans would be left to die. Not to mention all other life forms. (Maybe we'll bring cats, too?)

I'm not opposed to visiting Mars, but to do so under the claim that we could save humanity from disaster is utter folly.