And even with nuclear winter, super-volcano, giant meteorite or other extinction-level event, the least hospitable places on Earth still beat Mars. Sure, an ex

And even with nuclear winter, super-volcano, giant meteorite or other extinction-level event, the least hospitable places on Earth still beat Mars. Sure, an extra backup on Mars helps... but let's keep the backups we can do now, first. Also: spaceships... and tunnels. Next Elon enterprises should include underwater, Antartica or mountain-top habitats... and good practice for a Mars colony.