Elon Musk, the billionaire founder and CEO of the private spaceflight company SpaceX, wants to help establish a Mars colony of up to 80,000 people by ferrying explorers to the Red Planet for perhaps $500,000 a trip.
Relevant Sagan quote:
(...) we've put all our eggs in one basket. If we were on many worlds and were to mess up down here, there's a way for the human species to continue. I don't for a moment propose that the Earth is a disposable planet, and we have to put enormous efforts into making sure we don't muss up down here. But there is a chance.
This should also at least somewhat reduce the x-risk stemming from uFAI (a subset of uFAI's may not concern themselves with space travel), and may significantly reduce the x-risk posed by many other x-risk categories (bioengineered threats, catastrophic climate change, global nuclear catastrophe, grey goo scenarios, etcetera).
For total x-risk reduction, prima facie it's unclear to me how supporting an endeavor such as Musk's stacks up against the SI's effectiveness, measured by total x-risk reduction per donated currency unit.
What's your take?