Stephen Hawking argues in the recent book Starship Century that humans need to spread out into interstellar space in the next thousand years, or we're doomed. So over at Forbes, Elise Ackerman lays out three scenarios in which we could pay the immense cost of interstellar colonization.
Image via Merbel on CG Hub.
In a nutshell, her three options are: 1) Nationstates pool their resources in response to massive catastrophes. 2) Religious groups launch missionary projects to intelligent life elsewhere. 3) The economy grows to the point where the super-rich can afford to fund interstellar colonization on their own.
The whole thing is well worth reading. [Forbes]